diff --git a/Framework/API/test/WorkspaceFactoryTest.h b/Framework/API/test/WorkspaceFactoryTest.h
index 5874d0870cbe35be400565ec9ebe4e9800fba9c8..6a6a992231c26d52fb9a42974d89094b4272832d 100644
--- a/Framework/API/test/WorkspaceFactoryTest.h
+++ b/Framework/API/test/WorkspaceFactoryTest.h
@@ -56,13 +56,9 @@ public:
     MatrixWorkspace_sptr space;
     TS_ASSERT_THROWS_NOTHING(
         space = WorkspaceFactory::Instance().create("work", 1, 1, 1));
-    // clang-format off
-    DIAG_OFF(unused-value)
-    // clang-format on
+    DIAG_OFF("unused-value")
     TS_ASSERT_THROWS_NOTHING(dynamic_cast<WorkspaceTester *>(space.get()));
-    // clang-format off
-    DIAG_ON(unused-value)
-    // clang-format on
+    DIAG_ON("unused-value")
   }
 
   /** Make a parent, have the child be created with the same sizes */
diff --git a/Framework/CurveFitting/src/Functions/CrystalElectricField.cpp b/Framework/CurveFitting/src/Functions/CrystalElectricField.cpp
index d0dddaa4baeb77bb173e3fedea9a859403f5f283..6b3850162f4edb53daea9e44a18b35421f8fc612 100644
--- a/Framework/CurveFitting/src/Functions/CrystalElectricField.cpp
+++ b/Framework/CurveFitting/src/Functions/CrystalElectricField.cpp
@@ -17,9 +17,7 @@ namespace {
 
 // The missing braces warning is a false positive -
 // https://llvm.org/bugs/show_bug.cgi?id=21629
-// clang-format off
-DIAG_OFF(missing-braces)
-// clang-format on
+DIAG_OFF("missing-braces")
 
 // Get a complex conjugate of the value returned by
 // ComplexMatrix::operator(i,j)
@@ -636,9 +634,7 @@ void diagonalise(const ComplexFortranMatrix &hamiltonian,
   eigenvalues += -eshift;
 }
 
-// clang-format off
-DIAG_OFF(missing-braces)
-// clang-format on
+DIAG_OFF("missing-braces")
 
 } // anonymous namespace
 
diff --git a/Framework/DataObjects/inc/MantidDataObjects/MDGridBox.tcc b/Framework/DataObjects/inc/MantidDataObjects/MDGridBox.tcc
index 9e77d006f89686631e155586592dbc36195c7673..c3373bc4342faf1a1fd5f5ac2b6ec4d5219d901e 100644
--- a/Framework/DataObjects/inc/MantidDataObjects/MDGridBox.tcc
+++ b/Framework/DataObjects/inc/MantidDataObjects/MDGridBox.tcc
@@ -1286,9 +1286,7 @@ TMDE(void MDGridBox)::centroidSphere(API::CoordTransform &radiusTransform,
   } // (for each box)
 }
 //-----------------------------------------------------------------------------------------------
-// clang-format off
-DIAG_OFF(array-bounds)
-// clang-format on
+DIAG_OFF("array-bounds")
 /** Integrate the signal within a sphere; for example, to perform single-crystal
  * peak integration.
  * The CoordTransform object could be used for more complex shapes, e.g.
@@ -1492,9 +1490,7 @@ TMDE(void MDGridBox)::integrateCylinder(
   delete[] verticesContained;
   delete[] boxMightTouch;
 }
-// clang-format off
-DIAG_ON(array-bounds)
-// clang-format on
+DIAG_ON("array-bounds")
 
 /**
 Getter for the masking status of the gridded box.
diff --git a/Framework/DataObjects/src/MDHistoWorkspace.cpp b/Framework/DataObjects/src/MDHistoWorkspace.cpp
index e760c6f1c1f6f1e0586d851770612cf5ef01094e..1f6997f1a621634cc713dea53fa8cd17e98e4c09 100644
--- a/Framework/DataObjects/src/MDHistoWorkspace.cpp
+++ b/Framework/DataObjects/src/MDHistoWorkspace.cpp
@@ -1346,9 +1346,7 @@ uint64_t MDHistoWorkspace::sumNContribEvents() const {
 /**
  * Get the Q frame system (if any) to use.
 */
-// clang-format off
-DIAG_OFF(strict-aliasing)
-// clang-format on
+DIAG_OFF("strict-aliasing")
 Kernel::SpecialCoordinateSystem
 MDHistoWorkspace::getSpecialCoordinateSystem() const {
   MDFramesToSpecialCoordinateSystem converter;
diff --git a/Framework/Geometry/src/Objects/RuleItems.cpp b/Framework/Geometry/src/Objects/RuleItems.cpp
index fd64337e51017df2f924a693181a4dc376f9b520..bba6e3ff57a912c54a2f12f5f173bd30b45827d0 100644
--- a/Framework/Geometry/src/Objects/RuleItems.cpp
+++ b/Framework/Geometry/src/Objects/RuleItems.cpp
@@ -34,18 +34,14 @@
 #endif
 
 #include "MantidKernel/WarningSuppressions.h"
-// clang-format off
-DIAG_OFF(conversion)
-DIAG_OFF(cast-qual)
-// clang-format on
+DIAG_OFF("conversion")
+DIAG_OFF("cast-qual")
 #include <TopoDS_Shape.hxx>
 #include <BRepAlgoAPI_Common.hxx>
 #include <BRepAlgoAPI_Fuse.hxx>
 #include <BRepPrimAPI_MakeBox.hxx>
-// clang-format off
-DIAG_ON(conversion)
-DIAG_ON(cast-qual)
-// clang-format on
+DIAG_ON("conversion")
+DIAG_ON("cast-qual")
 #endif
 
 namespace Mantid {
diff --git a/Framework/Geometry/src/Rendering/GeometryTriangulator.cpp b/Framework/Geometry/src/Rendering/GeometryTriangulator.cpp
index 7ba3e7d1e4552c5a699fd75c3cda5e9e0ac12672..2b6a94ac185c6c16076ae505fe70d4f7cda28786 100644
--- a/Framework/Geometry/src/Rendering/GeometryTriangulator.cpp
+++ b/Framework/Geometry/src/Rendering/GeometryTriangulator.cpp
@@ -23,10 +23,9 @@
 #endif
 #endif
 
-// clang-format off
-DIAG_OFF(conversion)
-DIAG_OFF(cast-qual)
-// clang-format on
+DIAG_OFF("conversion")
+DIAG_OFF("cast-qual")
+
 #include <gp_Trsf.hxx>
 #include <gp_Pnt.hxx>
 #include <gp_Pln.hxx>
@@ -39,10 +38,8 @@ DIAG_OFF(cast-qual)
 #include <BRepBuilderAPI_Transform.hxx>
 #include <BRep_Tool.hxx>
 #include <Poly_Triangulation.hxx>
-// clang-format off
-DIAG_ON(conversion)
-DIAG_ON(cast-qual)
-// clang-format on
+DIAG_ON("conversion")
+DIAG_ON("cast-qual")
 
 #ifdef __INTEL_COMPILER
 #pragma warning enable 191
diff --git a/Framework/Geometry/src/Rendering/RenderingHelpers.cpp b/Framework/Geometry/src/Rendering/RenderingHelpers.cpp
index 76e17374af56cd8bf95307554535d6dce0266b16..7ad0c3ddcb8bb8b6d5353bd048f19457d9e9c04d 100644
--- a/Framework/Geometry/src/Rendering/RenderingHelpers.cpp
+++ b/Framework/Geometry/src/Rendering/RenderingHelpers.cpp
@@ -28,10 +28,9 @@
 #endif
 #endif
 
-// clang-format off
-DIAG_OFF(conversion)
-DIAG_OFF(cast-qual)
-// clang-format on
+DIAG_OFF("conversion")
+DIAG_OFF("cast-qual")
+
 #include <gp_Pnt.hxx>
 #include <TopoDS.hxx>
 #include <TopoDS_Shape.hxx>
@@ -41,10 +40,8 @@ DIAG_OFF(cast-qual)
 #include <Poly_Array1OfTriangle.hxx>
 #include <TColgp_Array1OfPnt.hxx>
 #include <Poly_Triangulation.hxx>
-// clang-format off
-DIAG_ON(conversion)
-DIAG_ON(cast-qual)
-// clang-format on
+DIAG_ON("conversion")
+DIAG_ON("cast-qual")
 
 #ifdef __INTEL_COMPILER
 #pragma warning enable 191
diff --git a/Framework/Geometry/src/Surfaces/Cone.cpp b/Framework/Geometry/src/Surfaces/Cone.cpp
index 111420ccd022130006d8d5118ca9c6af6be1133c..802b609219351b563827a155f93722130846c80e 100644
--- a/Framework/Geometry/src/Surfaces/Cone.cpp
+++ b/Framework/Geometry/src/Surfaces/Cone.cpp
@@ -30,15 +30,11 @@
 #endif
 
 #include "MantidKernel/WarningSuppressions.h"
-// clang-format off
-DIAG_OFF(conversion)
-DIAG_OFF(cast-qual)
-// clang-format on
+DIAG_OFF("conversion")
+DIAG_OFF("cast-qual")
 #include <BRepPrimAPI_MakeCone.hxx>
-// clang-format off
-DIAG_ON(conversion)
-DIAG_ON(cast-qual)
-// clang-format on
+DIAG_ON("conversion")
+DIAG_ON("cast-qual")
 #endif
 
 namespace Mantid {
diff --git a/Framework/Geometry/src/Surfaces/Cylinder.cpp b/Framework/Geometry/src/Surfaces/Cylinder.cpp
index d4af5cac27a05990e137b8963c177e4c6f7162be..f65ea3b17dafd414073f33283df9c4cbcdb51ca1 100644
--- a/Framework/Geometry/src/Surfaces/Cylinder.cpp
+++ b/Framework/Geometry/src/Surfaces/Cylinder.cpp
@@ -16,15 +16,11 @@
 #endif
 
 #include "MantidKernel/WarningSuppressions.h"
-// clang-format off
-DIAG_OFF(conversion)
-DIAG_OFF(cast-qual)
-// clang-format on
+DIAG_OFF("conversion")
+DIAG_OFF("cast-qual")
 #include <BRepPrimAPI_MakeCylinder.hxx>
-// clang-format off
-DIAG_ON(conversion)
-DIAG_ON(cast-qual)
-// clang-format on
+DIAG_ON("conversion")
+DIAG_ON("cast-qual")
 #endif
 
 namespace Mantid {
diff --git a/Framework/Geometry/src/Surfaces/Plane.cpp b/Framework/Geometry/src/Surfaces/Plane.cpp
index 1a84602898ac0b0282743bfd035a8d9f14284ee4..aebf83dc5d67ca479ce7d7d9dddafb42fcc2b713 100644
--- a/Framework/Geometry/src/Surfaces/Plane.cpp
+++ b/Framework/Geometry/src/Surfaces/Plane.cpp
@@ -17,19 +17,15 @@
 #endif
 
 #include "MantidKernel/WarningSuppressions.h"
-// clang-format off
-DIAG_OFF(conversion)
-DIAG_OFF(cast-qual)
-// clang-format on
+DIAG_OFF("conversion")
+DIAG_OFF("cast-qual")
 #include <BRepPrimAPI_MakeBox.hxx>
 #include <BRepBuilderAPI_MakeFace.hxx>
 #include <BRepPrimAPI_MakeHalfSpace.hxx>
 #include <BRepAlgoAPI_Common.hxx>
 #include <gp_Pln.hxx>
-// clang-format off
-DIAG_ON(conversion)
-DIAG_ON(cast-qual)
-// clang-format on
+DIAG_ON("conversion")
+DIAG_ON("cast-qual")
 #endif
 
 namespace Mantid {
diff --git a/Framework/Geometry/src/Surfaces/Sphere.cpp b/Framework/Geometry/src/Surfaces/Sphere.cpp
index 315f3a6881c20a80d3299cd13f356948387e473f..4269d6abecfa9fb770c0498124e9de559b0c97ca 100644
--- a/Framework/Geometry/src/Surfaces/Sphere.cpp
+++ b/Framework/Geometry/src/Surfaces/Sphere.cpp
@@ -14,15 +14,11 @@
 #endif
 
 #include "MantidKernel/WarningSuppressions.h"
-// clang-format off
-DIAG_OFF(conversion)
-DIAG_OFF(cast-qual)
-// clang-format on
+DIAG_OFF("conversion")
+DIAG_OFF("cast-qual")
 #include <BRepPrimAPI_MakeSphere.hxx>
-// clang-format off
-DIAG_ON(conversion)
-DIAG_ON(cast-qual)
-// clang-format on
+DIAG_ON("conversion")
+DIAG_ON("cast-qual")
 #endif
 
 namespace Mantid {
diff --git a/Framework/Geometry/src/Surfaces/Surface.cpp b/Framework/Geometry/src/Surfaces/Surface.cpp
index a2b436e85e90ff5436b0782725420bb7c758ebb6..292a82119d6c74cafaaf078f4f49719c6e44c013 100644
--- a/Framework/Geometry/src/Surfaces/Surface.cpp
+++ b/Framework/Geometry/src/Surfaces/Surface.cpp
@@ -29,15 +29,11 @@
 #endif
 
 #include "MantidKernel/WarningSuppressions.h"
-// clang-format off
-DIAG_OFF(conversion)
-DIAG_OFF(cast-qual)
-// clang-format on
+DIAG_OFF("conversion")
+DIAG_OFF("cast-qual")
 #include <TopoDS_Shape.hxx>
-// clang-format off
-DIAG_ON(conversion)
-DIAG_ON(cast-qual)
-// clang-format on
+DIAG_ON("conversion")
+DIAG_ON("cast-qual")
 #endif
 
 namespace Mantid {
diff --git a/Framework/Geometry/src/Surfaces/Torus.cpp b/Framework/Geometry/src/Surfaces/Torus.cpp
index 44025b8c3239e972a19f56c06cf7cdbbc81d8a06..635f7b1c51aea7fb29e2001ce2e9d444f9d8f351 100644
--- a/Framework/Geometry/src/Surfaces/Torus.cpp
+++ b/Framework/Geometry/src/Surfaces/Torus.cpp
@@ -29,15 +29,11 @@
 #endif
 
 #include "MantidKernel/WarningSuppressions.h"
-// clang-format off
-DIAG_OFF(conversion)
-DIAG_OFF(cast-qual)
-// clang-format on
+DIAG_OFF("conversion")
+DIAG_OFF("cast-qual")
 #include <TopoDS_Shape.hxx>
-// clang-format off
-DIAG_ON(conversion)
-DIAG_ON(cast-qual)
-// clang-format on
+DIAG_ON("conversion")
+DIAG_ON("cast-qual")
 #endif
 
 namespace Mantid {
diff --git a/Framework/Geometry/test/GroupTest.h b/Framework/Geometry/test/GroupTest.h
index c2a16693b781a55fbf6b19695984133fd38302f8..6ba6f52de0d72e7bdc94c3de9af637ec82999712 100644
--- a/Framework/Geometry/test/GroupTest.h
+++ b/Framework/Geometry/test/GroupTest.h
@@ -369,14 +369,10 @@ public:
 
     TS_ASSERT_THROWS(null * null, std::invalid_argument);
     // clang gives a warning if we don't use the result
-    // clang-format off
-    DIAG_OFF(unused-comparison)
-    // clang-format on
+    DIAG_OFF("unused-comparison")
     TS_ASSERT_THROWS(null == null, std::invalid_argument);
     TS_ASSERT_THROWS(null != null, std::invalid_argument);
-    // clang-format off
-    DIAG_ON(unused-comparison)
-    // clang-format on
+    DIAG_ON("unused-comparison")
     TS_ASSERT_THROWS(three * null, std::invalid_argument);
     TS_ASSERT_THROWS(null * three, std::invalid_argument);
 
diff --git a/Framework/ICat/src/CatalogSearch.cpp b/Framework/ICat/src/CatalogSearch.cpp
index ce89525405161acf4c0f7f6fa71bba0e44efed4c..fd37dcbf960686fb0c941666d6c7a42622fe7c91 100644
--- a/Framework/ICat/src/CatalogSearch.cpp
+++ b/Framework/ICat/src/CatalogSearch.cpp
@@ -1,13 +1,9 @@
 #if GCC_VERSION >= 40800 // 4.8.0
-// clang-format off
-DIAG_OFF(literal-suffix)
-// clang-format on
+DIAG_OFF("literal-suffix")
 #endif
 #include "MantidICat/CatalogSearch.h"
 #if GCC_VERSION >= 40800 // 4.8.0
-// clang-format off
-DIAG_ON(literal-suffix)
-// clang-format on
+DIAG_ON("literal-suffix")
 #endif
 
 #include "MantidAPI/CatalogManager.h"
diff --git a/Framework/ICat/src/GSoap.cpp b/Framework/ICat/src/GSoap.cpp
index f4c23869b1e716fa8077ab0220372833b24754f7..151efa097ae4735c4d32f4787a1e850c53008740 100644
--- a/Framework/ICat/src/GSoap.cpp
+++ b/Framework/ICat/src/GSoap.cpp
@@ -4,18 +4,14 @@
 // disable some warnings that we understand but do not want to touch as
 // it is automatically generated code
 //------------------------------------------------------------------------------
-// clang-format off
-DIAG_OFF(cast-qual)
-DIAG_OFF(conversion)
-DIAG_OFF(unused-parameter)
-DIAG_OFF(strict-aliasing)
-DIAG_OFF(format)
-DIAG_OFF(vla)
-// clang-format on
+DIAG_OFF("cast-qual")
+DIAG_OFF("conversion")
+DIAG_OFF("unused-parameter")
+DIAG_OFF("strict-aliasing")
+DIAG_OFF("format")
+DIAG_OFF("vla")
 #if GCC_VERSION >= 40800 // 4.8.0
-// clang-format off
-DIAG_OFF(literal-suffix)
-// clang-format on
+DIAG_OFF("literal-suffix")
 #endif
 #ifdef _WIN32
 #pragma warning(disable : 4100)
diff --git a/Framework/ICat/src/GSoap/stdsoap2.cpp b/Framework/ICat/src/GSoap/stdsoap2.cpp
index 3fef47ec183bf590b966f167b5436144f06be81a..881154361b02c2b1c070d66eda97f6585c347b92 100644
--- a/Framework/ICat/src/GSoap/stdsoap2.cpp
+++ b/Framework/ICat/src/GSoap/stdsoap2.cpp
@@ -3,13 +3,11 @@
 // ignore warnings in gSOAP
 // Long-term solution is to use gSOAP as an external library or external
 // project. see issue #19433
-// clang-format off
-DIAG_OFF(deprecated-declarations)
-DIAG_OFF(format-overflow)
-DIAG_OFF(format-truncation)
-DIAG_OFF(implicit-fallthrough)
-DIAG_OFF(cast-align)
-// clang-format on
+DIAG_OFF("deprecated-declarations")
+DIAG_OFF("format-overflow")
+DIAG_OFF("format-truncation")
+DIAG_OFF("implicit-fallthrough")
+DIAG_OFF("cast-align")
 
 /*
   stdsoap2.c[pp] 2.8.15
@@ -17016,10 +17014,8 @@ soap::~soap() {
 
 /******************************************************************************/
 
-// clang-format off
-DIAG_ON(deprecated-declarations)
-DIAG_ON(format-overflow)
-DIAG_ON(format-truncation)
-DIAG_ON(implicit-fallthrough)
-DIAG_ON(cast-align)
-// clang-format on
+DIAG_ON("deprecated-declarations")
+DIAG_ON("format-overflow")
+DIAG_ON("format-truncation")
+DIAG_ON("implicit-fallthrough")
+DIAG_ON("cast-align")
diff --git a/Framework/ICat/src/ICat3/ICat3GSoapGenerated.cpp b/Framework/ICat/src/ICat3/ICat3GSoapGenerated.cpp
index 0835075b17cd7d91046edfe875d6ad4e169a9dbe..63220d9b864e915118c4b83968a3f1953e865687 100644
--- a/Framework/ICat/src/ICat3/ICat3GSoapGenerated.cpp
+++ b/Framework/ICat/src/ICat3/ICat3GSoapGenerated.cpp
@@ -4,18 +4,14 @@
 // disable some warnings that we understand but do not want to touch as
 // it is automatically generated code
 //------------------------------------------------------------------------------
-// clang-format off
-DIAG_OFF(cast-qual)
-DIAG_OFF(conversion)
-DIAG_OFF(unused-parameter)
-DIAG_OFF(strict-aliasing)
-DIAG_OFF(format)
-DIAG_OFF(vla)
-// clang-format on
+DIAG_OFF("cast-qual")
+DIAG_OFF("conversion")
+DIAG_OFF("unused-parameter")
+DIAG_OFF("strict-aliasing")
+DIAG_OFF("format")
+DIAG_OFF("vla")
 #if GCC_VERSION >= 40800 // 4.8.0
-// clang-format off
-DIAG_OFF(literal-suffix)
-// clang-format on
+DIAG_OFF("literal-suffix")
 #endif
 #ifdef _WIN32
 #pragma warning(disable : 4100)
diff --git a/Framework/ICat/src/ICat3/ICat3Helper.cpp b/Framework/ICat/src/ICat3/ICat3Helper.cpp
index 1b9c9a846affec0525580a703cc1a229c3bd8144..b62a57971b46c3b1cef5d0b6f3415455f76f8d93 100644
--- a/Framework/ICat/src/ICat3/ICat3Helper.cpp
+++ b/Framework/ICat/src/ICat3/ICat3Helper.cpp
@@ -2,9 +2,7 @@
 // Poco-related compilation error on Windows
 #include "MantidAPI/WorkspaceFactory.h"
 #if GCC_VERSION >= 40800 // 4.8.0
-// clang-format off
-DIAG_OFF(literal-suffix)
-// clang-format on
+DIAG_OFF("literal-suffix")
 #endif
 #include "MantidICat/ICat3/ICat3Helper.h"
 #include "MantidICat/ICat3/ICat3ErrorHandling.h"
diff --git a/Framework/ICat/src/ICat4/ICat4GSoapGenerated.cpp b/Framework/ICat/src/ICat4/ICat4GSoapGenerated.cpp
index dc5885d73fb43720cd78cd79210df733d76dcc0f..c60417c89a94b2c840fb4ba43dc6c89881c6b35d 100644
--- a/Framework/ICat/src/ICat4/ICat4GSoapGenerated.cpp
+++ b/Framework/ICat/src/ICat4/ICat4GSoapGenerated.cpp
@@ -4,18 +4,14 @@
 // disable some warnings that we understand but do not want to touch as
 // it is automatically generated code
 //------------------------------------------------------------------------------
-// clang-format off
-DIAG_OFF(cast-qual)
-DIAG_OFF(conversion)
-DIAG_OFF(unused-parameter)
-DIAG_OFF(strict-aliasing)
-DIAG_OFF(format)
-DIAG_OFF(vla)
-// clang-format on
+DIAG_OFF("cast-qual")
+DIAG_OFF("conversion")
+DIAG_OFF("unused-parameter")
+DIAG_OFF("strict-aliasing")
+DIAG_OFF("format")
+DIAG_OFF("vla")
 #if GCC_VERSION >= 40800 // 4.8.0
-// clang-format off
-DIAG_OFF(literal-suffix)
-// clang-format on
+DIAG_OFF("literal-suffix")
 #endif
 #ifdef _WIN32
 #pragma warning(disable : 4100)
diff --git a/Framework/Kernel/inc/MantidKernel/PropertyHelper.h b/Framework/Kernel/inc/MantidKernel/PropertyHelper.h
index ad0e64d71191b74bc43f12223436955da383ed27..497361ba5c118c2ad6029e3c6f24584080595d08 100644
--- a/Framework/Kernel/inc/MantidKernel/PropertyHelper.h
+++ b/Framework/Kernel/inc/MantidKernel/PropertyHelper.h
@@ -124,9 +124,7 @@ std::string toPrettyString(
   }
   return Strings::shorten(retVal, maxLength);
 }
-// clang-format off
-DIAG_OFF(unused-function)
-// clang-format on
+DIAG_OFF("unused-function")
 /** Explicit specialization for a property of type std::vector<bool>.
 *   This will catch Vectors of char, double, float etc.
 *   This simply concatenates the values using a delimiter
@@ -141,9 +139,7 @@ std::string toPrettyString(
   return Strings::shorten(Strings::join(value.begin(), value.end(), delimiter),
                           maxLength);
 }
-// clang-format off
-DIAG_ON(unused-function)
-// clang-format on
+DIAG_ON("unused-function")
 
 /// Specialization for a property of type std::vector<std::vector>.
 template <typename T>
diff --git a/Framework/Kernel/inc/MantidKernel/WarningSuppressions.h b/Framework/Kernel/inc/MantidKernel/WarningSuppressions.h
index 3e6eaab2c1c51a326de6ef71d1b83f74a20d5f08..9a09737dcf85dc1ca24df6d70df8c8b59c9877f7 100644
--- a/Framework/Kernel/inc/MantidKernel/WarningSuppressions.h
+++ b/Framework/Kernel/inc/MantidKernel/WarningSuppressions.h
@@ -52,6 +52,7 @@
 #undef DIAG_JOINSTR
 #endif
 #define DIAG_JOINSTR(x, y) DIAG_STR(x##y)
+#define DIAG_MAKE_WARNING(x) "-W" x
 // undefine definition from Poco 1.6
 #ifdef DIAG_DO_PRAGMA
 #undef DIAG_DO_PRAGMA
@@ -80,16 +81,16 @@
 #if GCC_VERSION >= 40600 // GCC 4.6.0
 #define DIAG_OFF(x)                                                          \
   DIAG_PRAGMA(push)                                                          \
-  DIAG_PRAGMA(ignored DIAG_JOINSTR(-W, unknown-warning))                     \
-  DIAG_PRAGMA(ignored DIAG_JOINSTR(-W, x))
+  DIAG_PRAGMA(ignored DIAG_MAKE_WARNING("unknown-warning"))                     \
+  DIAG_PRAGMA(ignored DIAG_MAKE_WARNING(x))
 #define DIAG_ON(x) DIAG_PRAGMA(pop)
 #else
 #define DIAG_OFF(x)                                                          \
-  DIAG_PRAGMA(ignored DIAG_JOINSTR(-W, unknown-warning))                     \
-  DIAG_PRAGMA(ignored DIAG_JOINSTR(-W, x))
+  DIAG_PRAGMA(ignored DIAG_MAKE_WARNING("unknown-warning"))                     \
+  DIAG_PRAGMA(ignored DIAG_MAKE_WARNING(x))
 #define DIAG_ON(x)                                                           \
-  DIAG_PRAGMA(warning DIAG_JOINSTR(-W, unknown-warning))                     \
-  DIAG_PRAGMA(warning DIAG_JOINSTR(-W, x))
+  DIAG_PRAGMA(warning DIAG_MAKE_WARNING("unknown-warning"))                     \
+  DIAG_PRAGMA(warning DIAG_MAKE_WARNING(x))
 #endif
 // clang-format on
 
@@ -100,8 +101,8 @@
 // clang-format off
 #define DIAG_OFF(x)                                                         \
   DIAG_PRAGMA(push)                                                         \
-  DIAG_PRAGMA(ignored DIAG_JOINSTR(-W, unknown-warning-option))             \
-  DIAG_PRAGMA(ignored DIAG_JOINSTR(-W, x))
+  DIAG_PRAGMA(ignored DIAG_MAKE_WARNING("unknown-warning-option"))        \
+  DIAG_PRAGMA(ignored DIAG_MAKE_WARNING(x))
 #define DIAG_ON(x) DIAG_PRAGMA(pop)
 // clang-format on
 #else
@@ -116,11 +117,11 @@
 // the hyphen and we use it in a lot of test files.
 // clang-format off
 #if defined(__cplusplus) && defined(GCC_VERSION) && GCC_VERSION >= 50000
-#define DIAG_OFF_SUGGEST_OVERRIDE DIAG_OFF(suggest-override)
-#define DIAG_ON_SUGGEST_OVERRIDE DIAG_ON(suggest-override)
+#define DIAG_OFF_SUGGEST_OVERRIDE DIAG_OFF("suggest-override")
+#define DIAG_ON_SUGGEST_OVERRIDE DIAG_ON("suggest-override")
 #elif defined(__cplusplus) && defined(CLANG_VERSION) && CLANG_VERSION >= 306
-#define DIAG_OFF_SUGGEST_OVERRIDE DIAG_OFF(inconsistent-missing-override)
-#define DIAG_ON_SUGGEST_OVERRIDE DIAG_ON(inconsistent-missing-override)
+#define DIAG_OFF_SUGGEST_OVERRIDE DIAG_OFF("inconsistent-missing-override")
+#define DIAG_ON_SUGGEST_OVERRIDE DIAG_ON("inconsistent-missing-override")
 #else
 #define DIAG_OFF_SUGGEST_OVERRIDE
 #define DIAG_ON_SUGGEST_OVERRIDE
diff --git a/Framework/Kernel/inc/MantidKernel/normal_distribution.h b/Framework/Kernel/inc/MantidKernel/normal_distribution.h
index c7c304b1fcd2a0e220f9d74458f8074b026edc6a..206137705bd55a2bc9054b3850fe7adf67b5035f 100644
--- a/Framework/Kernel/inc/MantidKernel/normal_distribution.h
+++ b/Framework/Kernel/inc/MantidKernel/normal_distribution.h
@@ -170,9 +170,7 @@ public:
              normal_distribution<_RT> &__x);
 };
 
-// clang-format off
-DIAG_OFF(maybe-uninitialized)
-// clang-format on
+DIAG_OFF("maybe-uninitialized")
 template <class _RealType>
 template <class _URNG>
 _RealType normal_distribution<_RealType>::operator()(_URNG &__g,
@@ -198,9 +196,7 @@ _RealType normal_distribution<_RealType>::operator()(_URNG &__g,
   }
   return _Up * __p.stddev() + __p.mean();
 }
-// clang-format off
-DIAG_ON(maybe-uninitialized)
-// clang-format on
+DIAG_ON("maybe-uninitialized")
 
 template <class _CharT, class _Traits, class _RT>
 std::basic_ostream<_CharT, _Traits> &
diff --git a/Framework/LiveData/inc/MantidLiveData/ISIS/TCPEventStreamDefs.h b/Framework/LiveData/inc/MantidLiveData/ISIS/TCPEventStreamDefs.h
index 97e7f424fffd16e7811a8ad94bb53e617c12ff1a..a526e54eca77a9ca9f127fbfd6e77f5754eab664 100644
--- a/Framework/LiveData/inc/MantidLiveData/ISIS/TCPEventStreamDefs.h
+++ b/Framework/LiveData/inc/MantidLiveData/ISIS/TCPEventStreamDefs.h
@@ -9,9 +9,7 @@
 #include <vector>
 
 // to ignore warnings when comparing header versions
-// clang-format off
-DIAG_OFF(type-limits)
-// clang-format on
+DIAG_OFF("type-limits")
 #if defined(_WIN32)
 #pragma warning(disable : 4296)
 #endif
@@ -53,9 +51,7 @@ struct TCPStreamEventHeader {
       : marker1(marker), marker2(marker), version(current_version),
         length(sizeof(TCPStreamEventHeader)), type(type_) {}
 
-  // clang-format off
-  DIAG_OFF(autological-compare)
-  // clang-format on
+  DIAG_OFF("tautological-compare")
   bool isValid() const {
     return marker1 == marker && marker2 == marker &&
            length >= sizeof(TCPStreamEventHeader) &&
@@ -63,9 +59,7 @@ struct TCPStreamEventHeader {
            minorVersion() >= TCPStreamEventHeader::minor_version &&
            type != InvalidStream;
   }
-  // clang-format off
-  DIAG_ON(autological-compare)
-  // clang-format on
+  DIAG_ON("tautological-compare")
 
   static const uint32_t major_version =
       1; ///< starts at 1, then incremented whenever layout of this or further
@@ -195,7 +189,5 @@ struct TCPStreamEventDataSE {
 }
 }
 
-// clang-format off
-DIAG_ON(type-limits)
-// clang-format on
+DIAG_ON("type-limits")
 #endif /* TCP_EVENT_STREAM_DEFS_H */
diff --git a/Framework/LiveData/src/ISIS/ISISHistoDataListener.cpp b/Framework/LiveData/src/ISIS/ISISHistoDataListener.cpp
index e6ead5a47d939f1f90c669f987830880bae2bd3e..52ae216ef92a01674ed4337dd133dfb8eb68b9f9 100644
--- a/Framework/LiveData/src/ISIS/ISISHistoDataListener.cpp
+++ b/Framework/LiveData/src/ISIS/ISISHistoDataListener.cpp
@@ -21,9 +21,7 @@
 #ifdef GCC_VERSION
 // Avoid compiler warnings on gcc from unused static constants in
 // isisds_command.h
-// clang-format off
-DIAG_OFF(unused-variable)
-// clang-format on
+DIAG_OFF("unused-variable")
 #endif
 #include "DAE/idc.h"
 
diff --git a/Framework/LiveData/src/ISIS/ISISLiveEventDataListener.cpp b/Framework/LiveData/src/ISIS/ISISLiveEventDataListener.cpp
index ec5fa9a69a90c02e6a07633cdb1de356f943eccb..8911ed9bd8c830e42182fb729cfdc16e62837442 100644
--- a/Framework/LiveData/src/ISIS/ISISLiveEventDataListener.cpp
+++ b/Framework/LiveData/src/ISIS/ISISLiveEventDataListener.cpp
@@ -19,9 +19,7 @@
 #ifdef GCC_VERSION
 // Avoid compiler warnings on gcc from unused static constants in
 // isisds_command.h
-// clang-format off
-DIAG_OFF(unused-variable)
-// clang-format on
+DIAG_OFF("unused-variable")
 #endif
 #include "DAE/idc.h"
 
diff --git a/Framework/LiveData/src/Kafka/KafkaEventStreamDecoder.cpp b/Framework/LiveData/src/Kafka/KafkaEventStreamDecoder.cpp
index ce1c7af7835c730333458f1142c54f5048f37d04..5daea6c1e4b8ef262c255323bbd4314167e0b6fa 100644
--- a/Framework/LiveData/src/Kafka/KafkaEventStreamDecoder.cpp
+++ b/Framework/LiveData/src/Kafka/KafkaEventStreamDecoder.cpp
@@ -14,17 +14,13 @@
 #include "MantidLiveData/Exception.h"
 #include "MantidLiveData/Kafka/KafkaTopicSubscriber.h"
 
-// clang-format off
-DIAG_OFF(conversion)
-// clang-format on
+DIAG_OFF("conversion")
 #include "private/Schema/ba57_run_info_generated.h"
 #include "private/Schema/df12_det_spec_map_generated.h"
 #include "private/Schema/ev42_events_generated.h"
 #include "private/Schema/f142_logdata_generated.h"
 #include "private/Schema/is84_isis_events_generated.h"
-// clang-format off
-DIAG_ON(conversion)
-// clang-format on
+DIAG_ON("conversion")
 
 using namespace Mantid::Types;
 
diff --git a/Framework/LiveData/test/KafkaTesting.h b/Framework/LiveData/test/KafkaTesting.h
index e0e52f06a5c29def4303cac439b188964cfd680b..97bbfb17d5d6202b6405dd2c96b3ae76e4c2469f 100644
--- a/Framework/LiveData/test/KafkaTesting.h
+++ b/Framework/LiveData/test/KafkaTesting.h
@@ -8,17 +8,13 @@
 #include "MantidTypes/Core/DateAndTime.h"
 #include <gmock/gmock.h>
 
-// clang-format off
-DIAG_OFF(conversion)
-// clang-format on
+DIAG_OFF("conversion")
 #include "Kafka/private/Schema/ba57_run_info_generated.h"
 #include "Kafka/private/Schema/df12_det_spec_map_generated.h"
 #include "Kafka/private/Schema/ev42_events_generated.h"
 #include "Kafka/private/Schema/f142_logdata_generated.h"
 #include "Kafka/private/Schema/is84_isis_events_generated.h"
-// clang-format off
-DIAG_ON(conversion)
-// clang-format on
+DIAG_ON("conversion")
 
 #include <ctime>
 
diff --git a/Framework/MDAlgorithms/src/LoadSQW2.cpp b/Framework/MDAlgorithms/src/LoadSQW2.cpp
index 07855d71443970f0d6732d8c81117e63fa25b1db..68420602402ab32cc61b1951b955e82489117f20 100644
--- a/Framework/MDAlgorithms/src/LoadSQW2.cpp
+++ b/Framework/MDAlgorithms/src/LoadSQW2.cpp
@@ -485,9 +485,7 @@ std::vector<float> LoadSQW2::calculateDimLimitsFromData() {
 
 // The missing braces warning is a false positive -
 // https://llvm.org/bugs/show_bug.cgi?id=21629
-// clang-format off
-DIAG_OFF(missing-braces)
-// clang-format on
+DIAG_OFF("missing-braces")
 /**
  * Create the Q MDHistoDimension for the output frame and given information
  * from the file
@@ -541,9 +539,7 @@ LoadSQW2::createQDimension(size_t index, float dimMin, float dimMax,
   return builder.create();
 }
 
-// clang-format off
-DIAG_ON(missing-braces)
-// clang-format on
+DIAG_ON("missing-braces")
 
 /**
  * Create an energy dimension
diff --git a/Framework/MDAlgorithms/test/LoadSQW2Test.h b/Framework/MDAlgorithms/test/LoadSQW2Test.h
index 292a2d375e66e7db78001032c287f06dcf131407..529643da5ed586f0445fdb1f7dd26036c7009f6d 100644
--- a/Framework/MDAlgorithms/test/LoadSQW2Test.h
+++ b/Framework/MDAlgorithms/test/LoadSQW2Test.h
@@ -190,9 +190,7 @@ private:
     }
   }
 
-  // clang-format off
-  DIAG_OFF(missing-braces)
-  // clang-format on
+  DIAG_OFF("missing-braces")
   DimensionProperties getExpectedDimProperties(std::string outputFrame,
                                                DataType dtype) {
     DimensionProperties expected;
@@ -233,9 +231,7 @@ private:
     return expected;
   }
 
-  // clang-format off
-  DIAG_ON(missing-braces)
-  // clang-format on
+  DIAG_ON("missing-braces")
 
   void checkExperimentInfoAsExpected(const IMDEventWorkspace &outputWS) {
     TS_ASSERT_EQUALS(2, outputWS.getNumExperimentInfo());
diff --git a/Framework/PythonInterface/mantid/api/src/Exports/Algorithm.cpp b/Framework/PythonInterface/mantid/api/src/Exports/Algorithm.cpp
index 423f2c29b1f1bb63ef83f2031b2049e6291eeae1..5e8aff90eb1e1362507ad37674d899b7fb3a65ba 100644
--- a/Framework/PythonInterface/mantid/api/src/Exports/Algorithm.cpp
+++ b/Framework/PythonInterface/mantid/api/src/Exports/Algorithm.cpp
@@ -58,13 +58,11 @@ using declarePropertyType3 = void (*)(boost::python::object &,
 using declarePropertyType4 = void (*)(boost::python::object &,
                                       const std::string &,
                                       const boost::python::object &, const int);
-// clang-format off
-DIAG_OFF(unknown-pragmas)
-DIAG_OFF(unused-local-typdef)
+DIAG_OFF("unknown-pragmas")
+DIAG_OFF("unused-local-typdef")
 // Ignore -Wconversion warnings coming from boost::python
 // Seen with GCC 7.1.1 and Boost 1.63.0
-DIAG_OFF(conversion)
-// clang-format on
+DIAG_OFF("conversion")
 // Overload types
 BOOST_PYTHON_FUNCTION_OVERLOADS(declarePropertyType1_Overload,
                                 PythonAlgorithm::declarePyAlgProperty, 2, 3)
@@ -72,11 +70,10 @@ BOOST_PYTHON_FUNCTION_OVERLOADS(declarePropertyType2_Overload,
                                 PythonAlgorithm::declarePyAlgProperty, 3, 6)
 BOOST_PYTHON_FUNCTION_OVERLOADS(declarePropertyType3_Overload,
                                 PythonAlgorithm::declarePyAlgProperty, 4, 5)
-// clang-format off
-DIAG_ON(conversion)
-DIAG_ON(unknown-pragmas)
-DIAG_ON(unused-local-typdef)
-// clang-format on
+DIAG_ON("conversion")
+DIAG_ON("unknown-pragmas")
+DIAG_ON("unused-local-typdef")
+
 /**
  * Map a CancelException to a Python KeyboardInterupt
  * @param exc A cancel exception to translate. Unused here as the message is
diff --git a/Framework/PythonInterface/mantid/api/src/Exports/AlgorithmFactory.cpp b/Framework/PythonInterface/mantid/api/src/Exports/AlgorithmFactory.cpp
index b1b8c889f482ea7b61b7077749ae1dd4850ec196..56aff4917893f79bfeaae892922cd8fe0edf17f1 100644
--- a/Framework/PythonInterface/mantid/api/src/Exports/AlgorithmFactory.cpp
+++ b/Framework/PythonInterface/mantid/api/src/Exports/AlgorithmFactory.cpp
@@ -81,9 +81,7 @@ list getDescriptors(AlgorithmFactoryImpl &self, bool includeHidden) {
 // Python algorithm registration mutex in anonymous namespace (aka static)
 std::recursive_mutex PYALG_REGISTER_MUTEX;
 
-// clang-format off
-DIAG_OFF(cast-qual)
-// clang-format on
+DIAG_OFF("cast-qual")
 
 /**
  * A free function to subscribe a Python algorithm into the factory
@@ -119,25 +117,21 @@ void subscribe(AlgorithmFactoryImpl &self, const boost::python::object &obj) {
   FileLoaderRegistry::Instance().unsubscribe(descr.first, descr.second);
 }
 
-// clang-format off
-DIAG_OFF(unknown-pragmas)
-DIAG_OFF(unused-local-typdef)
+DIAG_OFF("unknown-pragmas")
+DIAG_OFF("unused-local-typdef")
 // Ignore -Wconversion warnings coming from boost::python
 // Seen with GCC 7.1.1 and Boost 1.63.0
-DIAG_OFF(conversion)
-// clang-format on
+DIAG_OFF("conversion")
+
 BOOST_PYTHON_MEMBER_FUNCTION_OVERLOADS(existsOverloader, exists, 1, 2)
-// clang-format off
-DIAG_ON(conversion)
-DIAG_ON(unknown-pragmas)
-DIAG_ON(unused-local-typdef)
-// clang-format on
+
+DIAG_ON("conversion")
+DIAG_ON("unknown-pragmas")
+DIAG_ON("unused-local-typdef")
 
 ///@endcond
 }
-// clang-format off
-DIAG_ON(cast-qual)
-// clang-format on
+DIAG_ON("cast-qual")
 
 void export_AlgorithmFactory() {
 
diff --git a/Framework/PythonInterface/mantid/api/src/Exports/AlgorithmManager.cpp b/Framework/PythonInterface/mantid/api/src/Exports/AlgorithmManager.cpp
index a0587d8cb71b72160b2095eccdf6cb7f69b2f573..4f3664d63b37fb67c4130871ab69d84c104968d2 100644
--- a/Framework/PythonInterface/mantid/api/src/Exports/AlgorithmManager.cpp
+++ b/Framework/PythonInterface/mantid/api/src/Exports/AlgorithmManager.cpp
@@ -56,24 +56,20 @@ boost::python::list runningInstancesOf(AlgorithmManagerImpl &self,
 
 ///@cond
 //------------------------------------------------------------------------------------------------------
-// clang-format off
-DIAG_OFF(unknown-pragmas)
-DIAG_OFF(unused-local-typdef)
+DIAG_OFF("unknown-pragmas")
+DIAG_OFF("unused-local-typdef")
 // Ignore -Wconversion warnings coming from boost::python
 // Seen with GCC 7.1.1 and Boost 1.63.0
-DIAG_OFF(conversion)
-// clang-format on
+DIAG_OFF("conversion")
 /// Define overload generators
 BOOST_PYTHON_MEMBER_FUNCTION_OVERLOADS(create_overloads,
                                        AlgorithmManagerImpl::create, 1, 2)
 BOOST_PYTHON_MEMBER_FUNCTION_OVERLOADS(createUnmanaged_overloads,
                                        AlgorithmManagerImpl::createUnmanaged, 1,
                                        2)
-// clang-format off
-DIAG_ON(conversion)
-DIAG_ON(unknown-pragmas)
-DIAG_ON(unused-local-typdef)
-// clang-format on
+DIAG_ON("conversion")
+DIAG_ON("unknown-pragmas")
+DIAG_ON("unused-local-typdef")
 ///@endcond
 }
 
diff --git a/Framework/PythonInterface/mantid/api/src/Exports/Axis.cpp b/Framework/PythonInterface/mantid/api/src/Exports/Axis.cpp
index 2a32a21e5da1658987bfba72b77ce4cb11d92f72..56b731e0510a901ec1f6b10452a2ac732157f609 100644
--- a/Framework/PythonInterface/mantid/api/src/Exports/Axis.cpp
+++ b/Framework/PythonInterface/mantid/api/src/Exports/Axis.cpp
@@ -29,20 +29,18 @@ GET_POINTER_SPECIALIZATION(Axis)
 namespace {
 
 //------------------------------- Overload macros ---------------------------
-// clang-format off
-DIAG_OFF(unknown-pragmas)
-DIAG_OFF(unused-local-typdef)
+DIAG_OFF("unknown-pragmas")
+DIAG_OFF("unused-local-typdef")
 // Ignore -Wconversion warnings coming from boost::python
 // Seen with GCC 7.1.1 and Boost 1.63.0
-DIAG_OFF(conversion)
-// clang-format on
+DIAG_OFF("conversion")
+
 // Overloads for operator() function which has 1 optional argument
 BOOST_PYTHON_MEMBER_FUNCTION_OVERLOADS(Axis_getValue, Axis::getValue, 1, 2)
-// clang-format off
-DIAG_ON(conversion)
-DIAG_ON(unknown-pragmas)
-DIAG_ON(unused-local-typdef)
-// clang-format on
+
+DIAG_ON("conversion")
+DIAG_ON("unknown-pragmas")
+DIAG_ON("unused-local-typdef")
 /**
  * Extract the axis values as a sequence. A numpy array is used if the
  * data is numerical or a simple python list is used if the data is a string
diff --git a/Framework/PythonInterface/mantid/api/src/Exports/CompositeFunction.cpp b/Framework/PythonInterface/mantid/api/src/Exports/CompositeFunction.cpp
index f850a9fe7f913c754c4a029f734917fe1e756f51..be62f9387cac756bf15674dca8229b4460e6898e 100644
--- a/Framework/PythonInterface/mantid/api/src/Exports/CompositeFunction.cpp
+++ b/Framework/PythonInterface/mantid/api/src/Exports/CompositeFunction.cpp
@@ -19,18 +19,15 @@ using getParameterType2 =
 
 using setParameterType2 = void (CompositeFunction::*)(const std::string &,
                                                       const double &, bool);
-// clang-format off
-DIAG_OFF(unknown-pragmas)
-DIAG_OFF(unused-local-typdef)
-DIAG_OFF(conversion)
-// clang-format on
+DIAG_OFF("unknown-pragmas")
+DIAG_OFF("unused-local-typdef")
+DIAG_OFF("conversion")
+
 BOOST_PYTHON_MEMBER_FUNCTION_OVERLOADS(setParameterType2_Overloads,
                                        setParameter, 2, 3)
-// clang-format off
-DIAG_ON(conversion)
-DIAG_ON(unknown-pragmas)
-DIAG_ON(unused-local-typdef)
-// clang-format on
+DIAG_ON("conversion")
+DIAG_ON("unknown-pragmas")
+DIAG_ON("unused-local-typdef")
 } // namespace
 
 void export_CompositeFunction() {
diff --git a/Framework/PythonInterface/mantid/api/src/Exports/ExperimentInfo.cpp b/Framework/PythonInterface/mantid/api/src/Exports/ExperimentInfo.cpp
index 32325425ed86db99bbc27b401e62f6a7dadaba3b..dab723c160c88f94192fa29c30b9bc5c88d6d580 100644
--- a/Framework/PythonInterface/mantid/api/src/Exports/ExperimentInfo.cpp
+++ b/Framework/PythonInterface/mantid/api/src/Exports/ExperimentInfo.cpp
@@ -18,21 +18,17 @@ using namespace boost::python;
 
 GET_POINTER_SPECIALIZATION(ExperimentInfo)
 
-// clang-format off
-DIAG_OFF(unknown-pragmas)
-DIAG_OFF(unused-local-typdef)
+DIAG_OFF("unknown-pragmas")
+DIAG_OFF("unused-local-typdef")
 // Ignore -Wconversion warnings coming from boost::python
 // Seen with GCC 7.1.1 and Boost 1.63.0
-DIAG_OFF(conversion)
-// clang-format on
+DIAG_OFF("conversion")
 /// Overload generator for getInstrumentFilename
 BOOST_PYTHON_FUNCTION_OVERLOADS(getInstrumentFilename_Overload,
                                 ExperimentInfo::getInstrumentFilename, 1, 2)
-// clang-format off
-DIAG_ON(conversion)
-DIAG_ON(unknown-pragmas)
-DIAG_ON(unused-local-typdef)
-// clang-format on
+DIAG_ON("conversion")
+DIAG_ON("unknown-pragmas")
+DIAG_ON("unused-local-typdef")
 
 void export_ExperimentInfo() {
   register_ptr_to_python<boost::shared_ptr<ExperimentInfo>>();
diff --git a/Framework/PythonInterface/mantid/api/src/Exports/FileFinder.cpp b/Framework/PythonInterface/mantid/api/src/Exports/FileFinder.cpp
index 26f6be43d65bd5936d5586543947429345ae0805..de9a731bdf0248dba94f15a42367438d1914f8ab 100644
--- a/Framework/PythonInterface/mantid/api/src/Exports/FileFinder.cpp
+++ b/Framework/PythonInterface/mantid/api/src/Exports/FileFinder.cpp
@@ -9,19 +9,17 @@ using Mantid::API::FileFinderImpl;
 using namespace boost::python;
 
 namespace {
-// clang-format off
-DIAG_OFF(unknown-pragmas)
-DIAG_OFF(unused-local-typdef)
+DIAG_OFF("unknown-pragmas")
+DIAG_OFF("unused-local-typdef")
 // Ignore -Wconversion warnings coming from boost::python
 // Seen with GCC 7.1.1 and Boost 1.63.0
-DIAG_OFF(conversion)
-// clang-format on
+DIAG_OFF("conversion")
+
 BOOST_PYTHON_MEMBER_FUNCTION_OVERLOADS(getFullPathOverloader, getFullPath, 1, 2)
-// clang-format off
-DIAG_ON(conversion)
-DIAG_ON(unknown-pragmas)
-DIAG_ON(unused-local-typdef)
-// clang-format on
+
+DIAG_ON("conversion")
+DIAG_ON("unknown-pragmas")
+DIAG_ON("unused-local-typdef")
 }
 
 void export_FileFinder() {
diff --git a/Framework/PythonInterface/mantid/api/src/Exports/IFunction.cpp b/Framework/PythonInterface/mantid/api/src/Exports/IFunction.cpp
index 0a0bf2692b468a0f71c0986fbc88ae3bebbeea17..b75f9433a52c7c655792d86052887ba38a01c8f8 100644
--- a/Framework/PythonInterface/mantid/api/src/Exports/IFunction.cpp
+++ b/Framework/PythonInterface/mantid/api/src/Exports/IFunction.cpp
@@ -50,13 +50,12 @@ double getError(IFunction &self, std::string const &name) {
 // -- Set property overloads --
 // setProperty(index,value,explicit)
 using setParameterType1 = void (IFunction::*)(size_t, const double &, bool);
-// clang-format off
-DIAG_OFF(unknown-pragmas)
-DIAG_OFF(unused-local-typdef)
+DIAG_OFF("unknown-pragmas")
+DIAG_OFF("unused-local-typdef")
 // Ignore -Wconversion warnings coming from boost::python
 // Seen with GCC 7.1.1 and Boost 1.63.0
-DIAG_OFF(conversion)
-// clang-format on
+DIAG_OFF("conversion")
+
 BOOST_PYTHON_MEMBER_FUNCTION_OVERLOADS(setParameterType1_Overloads,
                                        setParameter, 2, 3)
 // setProperty(index,value,explicit)
@@ -73,11 +72,9 @@ BOOST_PYTHON_MEMBER_FUNCTION_OVERLOADS(fix_Overloads, fix, 1, 2)
 BOOST_PYTHON_MEMBER_FUNCTION_OVERLOADS(fixAll_Overloads, fixAll, 0, 1)
 using removeTieByName = void (IFunction::*)(const std::string &);
 
-// clang-format off
-DIAG_ON(conversion)
-DIAG_ON(unknown-pragmas)
-DIAG_ON(unused-local-typdef)
-// clang-format on
+DIAG_ON("conversion")
+DIAG_ON("unknown-pragmas")
+DIAG_ON("unused-local-typdef")
 ///@endcond
 }
 
diff --git a/Framework/PythonInterface/mantid/api/src/Exports/IMaskWorkspace.cpp b/Framework/PythonInterface/mantid/api/src/Exports/IMaskWorkspace.cpp
index e03233f2ace1dd26dc52b91b7e7435f7d5380196..40fc4b31474b808d4aa30082627339bf948aabdd 100644
--- a/Framework/PythonInterface/mantid/api/src/Exports/IMaskWorkspace.cpp
+++ b/Framework/PythonInterface/mantid/api/src/Exports/IMaskWorkspace.cpp
@@ -6,9 +6,7 @@
 #include <boost/python/extract.hpp>
 #include <boost/python/list.hpp>
 
-// clang-format off
-DIAG_OFF(strict-aliasing)
-// clang-format on
+DIAG_OFF("strict-aliasing")
 
 using Mantid::API::IMaskWorkspace;
 using namespace Mantid::PythonInterface::Registry;
diff --git a/Framework/PythonInterface/mantid/api/src/Exports/MatrixWorkspace.cpp b/Framework/PythonInterface/mantid/api/src/Exports/MatrixWorkspace.cpp
index 389f63f20ccdde5aecbfe70f06fa380db51d083b..c2ed21d751638f4698bf460451920b60b885d0e5 100644
--- a/Framework/PythonInterface/mantid/api/src/Exports/MatrixWorkspace.cpp
+++ b/Framework/PythonInterface/mantid/api/src/Exports/MatrixWorkspace.cpp
@@ -49,21 +49,17 @@ using return_readwrite_numpy =
     return_value_policy<VectorRefToNumpy<WrapReadWrite>>;
 
 //------------------------------- Overload macros ---------------------------
-// clang-format off
-DIAG_OFF(unknown-pragmas)
-DIAG_OFF(unused-local-typdef)
+DIAG_OFF("unknown-pragmas")
+DIAG_OFF("unused-local-typdef")
 // Ignore -Wconversion warnings coming from boost::python
 // Seen with GCC 7.1.1 and Boost 1.63.0
-DIAG_OFF(conversion)
-// clang-format on
+DIAG_OFF("conversion")
 // Overloads for binIndexOf function which has 1 optional argument
 BOOST_PYTHON_MEMBER_FUNCTION_OVERLOADS(MatrixWorkspace_binIndexOfOverloads,
                                        MatrixWorkspace::binIndexOf, 1, 2)
-// clang-format off
-DIAG_ON(conversion)
-DIAG_ON(unknown-pragmas)
-DIAG_ON(unused-local-typdef)
-// clang-format on
+DIAG_ON("conversion")
+DIAG_ON("unknown-pragmas")
+DIAG_ON("unused-local-typdef")
 
 /**
  * Set the values from an python array-style object into the given spectrum in
diff --git a/Framework/PythonInterface/mantid/api/src/Exports/Projection.cpp b/Framework/PythonInterface/mantid/api/src/Exports/Projection.cpp
index 0239146f3f5adc5ed4837fbeb47cf7a29135168d..86b8357d3e7446900add592326bab4a0d5b97f86 100644
--- a/Framework/PythonInterface/mantid/api/src/Exports/Projection.cpp
+++ b/Framework/PythonInterface/mantid/api/src/Exports/Projection.cpp
@@ -14,9 +14,8 @@
 using namespace Mantid::API;
 using namespace Mantid::PythonInterface;
 using namespace boost::python;
-// clang-format off
-DIAG_OFF(strict-aliasing)
-// clang-format on
+
+DIAG_OFF("strict-aliasing")
 
 namespace {
 std::string getUnit(Projection &p, size_t nd) {
diff --git a/Framework/PythonInterface/mantid/api/src/Exports/Run.cpp b/Framework/PythonInterface/mantid/api/src/Exports/Run.cpp
index dcb42b1665530c0f7ee3f293f1ba2bbe9e6471f1..4a62e3da0a411d781821a8f761dc430ab02c471f 100644
--- a/Framework/PythonInterface/mantid/api/src/Exports/Run.cpp
+++ b/Framework/PythonInterface/mantid/api/src/Exports/Run.cpp
@@ -115,20 +115,17 @@ bpl::list keys(Run &self) {
   return names;
 }
 }
-// clang-format off
-DIAG_OFF(unknown-pragmas)
-DIAG_OFF(unused-local-typdef)
+DIAG_OFF("unknown-pragmas")
+DIAG_OFF("unused-local-typdef")
 // Ignore -Wconversion warnings coming from boost::python
 // Seen with GCC 7.1.1 and Boost 1.63.0
-DIAG_OFF(conversion)
-// clang-format on
+DIAG_OFF("conversion")
+
 BOOST_PYTHON_MEMBER_FUNCTION_OVERLOADS(integrateProtonCharge_Overload,
                                        integrateProtonCharge, 0, 1)
-// clang-format off
-DIAG_ON(conversion)
-DIAG_ON(unknown-pragmas)
-DIAG_ON(unused-local-typdef)
-// clang-format on
+DIAG_ON("conversion")
+DIAG_ON("unknown-pragmas")
+DIAG_ON("unused-local-typdef")
 
 void export_Run() {
   // Pointer
diff --git a/Framework/PythonInterface/mantid/api/src/Exports/Workspace.cpp b/Framework/PythonInterface/mantid/api/src/Exports/Workspace.cpp
index 227f9999e6cd250ab28b43dfe1e286c9af57e275..3723d3630e63c3fbe64798e1a6884512a1c92a4a 100644
--- a/Framework/PythonInterface/mantid/api/src/Exports/Workspace.cpp
+++ b/Framework/PythonInterface/mantid/api/src/Exports/Workspace.cpp
@@ -19,20 +19,16 @@ GET_POINTER_SPECIALIZATION(Workspace)
 
 namespace {
 ///@cond
-// clang-format off
-DIAG_OFF(unknown-pragmas)
-DIAG_OFF(unused-local-typdef)
+DIAG_OFF("unknown-pragmas")
+DIAG_OFF("unused-local-typdef")
 // Ignore -Wconversion warnings coming from boost::python
 // Seen with GCC 7.1.1 and Boost 1.63.0
-DIAG_OFF(conversion)
-// clang-format on
+DIAG_OFF("conversion")
 BOOST_PYTHON_MEMBER_FUNCTION_OVERLOADS(Workspace_isDirtyOverloads,
                                        Workspace::isDirty, 0, 1)
-// clang-format off
-DIAG_ON(conversion)
-DIAG_ON(unknown-pragmas)
-DIAG_ON(unused-local-typdef)
-// clang-format on
+DIAG_ON("conversion")
+DIAG_ON("unknown-pragmas")
+DIAG_ON("unused-local-typdef")
 
 ///@endcond
 }
diff --git a/Framework/PythonInterface/mantid/api/src/Exports/WorkspaceFactory.cpp b/Framework/PythonInterface/mantid/api/src/Exports/WorkspaceFactory.cpp
index 9561fa83a4e40b53c434dfade43aa12bbdb7f089..67a79033bcb8b4d64cc82bb36dc98a205f7668f6 100644
--- a/Framework/PythonInterface/mantid/api/src/Exports/WorkspaceFactory.cpp
+++ b/Framework/PythonInterface/mantid/api/src/Exports/WorkspaceFactory.cpp
@@ -46,22 +46,20 @@ Workspace_sptr createFromParentPtr(WorkspaceFactoryImpl &self,
 }
 
 /// Overload generator for create
-// clang-format off
-DIAG_OFF(unknown-pragmas)
-DIAG_OFF(unused-local-typdef)
+DIAG_OFF("unknown-pragmas")
+DIAG_OFF("unused-local-typdef")
 // Ignore -Wconversion warnings coming from boost::python
 // Seen with GCC 7.1.1 and Boost 1.63.0
-DIAG_OFF(conversion)
-// clang-format on
+DIAG_OFF("conversion")
+
 BOOST_PYTHON_FUNCTION_OVERLOADS(createFromParent_Overload, createFromParentPtr,
                                 2, 5)
 BOOST_PYTHON_MEMBER_FUNCTION_OVERLOADS(createTable_Overload, createTable, 0, 1)
 BOOST_PYTHON_MEMBER_FUNCTION_OVERLOADS(createPeaks_Overload, createPeaks, 0, 1)
-// clang-format off
-DIAG_ON(conversion)
-DIAG_ON(unknown-pragmas)
-DIAG_ON(unused-local-typdef)
-// clang-format on
+
+DIAG_ON("conversion")
+DIAG_ON("unknown-pragmas")
+DIAG_ON("unused-local-typdef")
 }
 
 void export_WorkspaceFactory() {
diff --git a/Framework/PythonInterface/mantid/api/src/PythonAlgorithm/AlgorithmAdapter.cpp b/Framework/PythonInterface/mantid/api/src/PythonAlgorithm/AlgorithmAdapter.cpp
index c20274fd4ae17ec16fcf6b3945a1945181960b14..6041a58a8d1c3c4265997cb21bde8f6b1aa4fd16 100644
--- a/Framework/PythonInterface/mantid/api/src/PythonAlgorithm/AlgorithmAdapter.cpp
+++ b/Framework/PythonInterface/mantid/api/src/PythonAlgorithm/AlgorithmAdapter.cpp
@@ -147,9 +147,7 @@ bool AlgorithmAdapter<BaseAlgorithm>::isRunning() const {
   } else {
     Environment::GlobalInterpreterLock gil;
 
-    // clang-format off
-    DIAG_OFF(parentheses-equality)
-    // clang-format on
+    DIAG_OFF("parentheses-equality")
     PyObject *result = PyObject_CallObject(m_isRunningObj, nullptr);
     if (PyErr_Occurred())
       throw Environment::PythonException();
@@ -165,9 +163,7 @@ bool AlgorithmAdapter<BaseAlgorithm>::isRunning() const {
       throw std::runtime_error(
           "Algorithm.isRunning - Expected bool return type.");
   }
-  // clang-format off
-  DIAG_ON(parentheses-equality)
-  // clang-format on
+  DIAG_ON("parentheses-equality")
 }
 
 /**
diff --git a/Framework/PythonInterface/mantid/geometry/src/Exports/Component.cpp b/Framework/PythonInterface/mantid/geometry/src/Exports/Component.cpp
index 489bb6f33408d0c3d6308f34373dd01491133458..1e977c6a8c992cd3710b1127d4669a64f42668c5 100644
--- a/Framework/PythonInterface/mantid/geometry/src/Exports/Component.cpp
+++ b/Framework/PythonInterface/mantid/geometry/src/Exports/Component.cpp
@@ -8,14 +8,11 @@ using Mantid::Geometry::IComponent;
 using namespace boost::python;
 
 namespace {
-// clang-format off
-DIAG_OFF(unknown-pragmas)
-DIAG_OFF(unused-local-typdef)
-
+DIAG_OFF("unknown-pragmas")
+DIAG_OFF("unused-local-typdef")
 // Ignore -Wconversion warnings coming from boost::python
 // Seen with GCC 7.1.1 and Boost 1.63.0
-DIAG_OFF(conversion)
-// clang-format on
+DIAG_OFF("conversion")
 
 // Default parameter function overloads
 BOOST_PYTHON_MEMBER_FUNCTION_OVERLOADS(Component_getParameterNames,
@@ -46,11 +43,9 @@ BOOST_PYTHON_MEMBER_FUNCTION_OVERLOADS(Component_getParamShortDescription,
 BOOST_PYTHON_MEMBER_FUNCTION_OVERLOADS(Component_getParamDescription,
                                        Component::getParamDescription, 1, 2)
 
-// clang-format off
-DIAG_ON(conversion)
-DIAG_ON(unknown-pragmas)
-DIAG_ON(unused-local-typdef)
-// clang-format on
+DIAG_ON("conversion")
+DIAG_ON("unknown-pragmas")
+DIAG_ON("unused-local-typdef")
 }
 void export_Component() {
   class_<Component, bases<IComponent>, boost::noncopyable>("Component", no_init)
diff --git a/Framework/PythonInterface/mantid/geometry/src/Exports/Goniometer.cpp b/Framework/PythonInterface/mantid/geometry/src/Exports/Goniometer.cpp
index 0797ea91273e5ea0cf3c206bee30651d995155c5..fd911aec5070ea999a17a9eba5e3759bc8f9e32e 100644
--- a/Framework/PythonInterface/mantid/geometry/src/Exports/Goniometer.cpp
+++ b/Framework/PythonInterface/mantid/geometry/src/Exports/Goniometer.cpp
@@ -16,21 +16,17 @@ using namespace boost::python;
 namespace //<unnamed>
     {
 ///@cond
-// clang-format off
-DIAG_OFF(unknown-pragmas)
-DIAG_OFF(unused-local-typdef)
+DIAG_OFF("unknown-pragmas")
+DIAG_OFF("unused-local-typdef")
 // Ignore -Wconversion warnings coming from boost::python
 // Seen with GCC 7.1.1 and Boost 1.63.0
-DIAG_OFF(conversion)
-// clang-format on
+DIAG_OFF("conversion")
 // define overloaded functions
 BOOST_PYTHON_MEMBER_FUNCTION_OVERLOADS(getEulerAngles_overloads,
                                        Goniometer::getEulerAngles, 0, 1)
-// clang-format off
-DIAG_ON(conversion)
-DIAG_ON(unknown-pragmas)
-DIAG_ON(unused-local-typdef)
-// clang-format on
+DIAG_ON("conversion")
+DIAG_ON("unknown-pragmas")
+DIAG_ON("unused-local-typdef")
 ///@endcond
 
 /// Set the U vector via a numpy array
diff --git a/Framework/PythonInterface/mantid/geometry/src/Exports/IMDDimension.cpp b/Framework/PythonInterface/mantid/geometry/src/Exports/IMDDimension.cpp
index e4a1c6c3fdd567137a8e11c90d44e361d14596e2..434faa02f5774069f09b55d9ece49d1b39b2e1f3 100644
--- a/Framework/PythonInterface/mantid/geometry/src/Exports/IMDDimension.cpp
+++ b/Framework/PythonInterface/mantid/geometry/src/Exports/IMDDimension.cpp
@@ -15,9 +15,7 @@ using namespace boost::python;
 
 GET_POINTER_SPECIALIZATION(IMDDimension)
 
-// clang-format off
-DIAG_OFF(strict-aliasing)
-// clang-format on
+DIAG_OFF("strict-aliasing")
 
 namespace {
 /**
diff --git a/Framework/PythonInterface/mantid/kernel/src/Converters/DateAndTime.cpp b/Framework/PythonInterface/mantid/kernel/src/Converters/DateAndTime.cpp
index 461f2ad161667560bd615fd1819fb062dc6144b2..a161d2e067db4e3e606ba887fb360cef4fd70d71 100644
--- a/Framework/PythonInterface/mantid/kernel/src/Converters/DateAndTime.cpp
+++ b/Framework/PythonInterface/mantid/kernel/src/Converters/DateAndTime.cpp
@@ -47,13 +47,9 @@ PyArray_Descr *descr_ns() { return func_PyArray_Descr("M8[ns]"); }
 // internal function that handles raw pointer
 boost::shared_ptr<Types::Core::DateAndTime>
 to_dateandtime(const PyObject *datetime) {
-  // clang-format off
-DIAG_OFF(cast-qual)
-  // clang-format on
+DIAG_OFF("cast-qual")
   if (!PyArray_IsScalar(datetime, Datetime)) {
-    // clang-format off
-DIAG_ON(cast-qual)
-    // clang-format on
+DIAG_ON("cast-qual")
     throw std::runtime_error("Expected datetime64");
   }
 
diff --git a/Framework/PythonInterface/mantid/kernel/src/Converters/PyObjectToVMD.cpp b/Framework/PythonInterface/mantid/kernel/src/Converters/PyObjectToVMD.cpp
index 8f7c008549c254f2dbee9116b284592c56223bf1..21714b24d79ce87f9d24bf51e6fc5317c79e9486 100644
--- a/Framework/PythonInterface/mantid/kernel/src/Converters/PyObjectToVMD.cpp
+++ b/Framework/PythonInterface/mantid/kernel/src/Converters/PyObjectToVMD.cpp
@@ -15,9 +15,7 @@ using boost::python::extract;
 using boost::python::object;
 using boost::python::len;
 
-// clang-format off
-DIAG_OFF(strict-aliasing)
-// clang-format on
+DIAG_OFF("strict-aliasing")
 
 namespace Mantid {
 namespace PythonInterface {
diff --git a/Framework/PythonInterface/mantid/kernel/src/Exports/ConfigService.cpp b/Framework/PythonInterface/mantid/kernel/src/Exports/ConfigService.cpp
index 96d1149cdc97b0a58684b9dee360a2610852cb79..3ccd748bc939e3ee8c25631ac593ccfd0860c041 100644
--- a/Framework/PythonInterface/mantid/kernel/src/Exports/ConfigService.cpp
+++ b/Framework/PythonInterface/mantid/kernel/src/Exports/ConfigService.cpp
@@ -32,23 +32,20 @@ std::string getStringUsingCache(ConfigServiceImpl &self,
   return self.getString(key, true);
 }
 
-// clang-format off
-DIAG_OFF(unknown-pragmas)
-DIAG_OFF(unused-local-typdef)
+DIAG_OFF("unknown-pragmas")
+DIAG_OFF("unused-local-typdef")
 // Ignore -Wconversion warnings coming from boost::python
 // Seen with GCC 7.1.1 and Boost 1.63.0
-DIAG_OFF(conversion)
-// clang-format on
+DIAG_OFF("conversion")
 /// Overload generator for getInstrument
 BOOST_PYTHON_MEMBER_FUNCTION_OVERLOADS(getInstrument_Overload, getInstrument, 0,
                                        1)
 /// Overload generator for getString
 BOOST_PYTHON_MEMBER_FUNCTION_OVERLOADS(getString_Overload, getString, 1, 2)
-// clang-format off
-DIAG_ON(conversion)
-DIAG_ON(unknown-pragmas)
-DIAG_ON(unused-local-typdef)
-// clang-format on
+
+DIAG_ON("conversion")
+DIAG_ON("unknown-pragmas")
+DIAG_ON("unused-local-typdef")
 }
 
 void export_ConfigService() {
diff --git a/Framework/PythonInterface/mantid/kernel/src/Exports/Property.cpp b/Framework/PythonInterface/mantid/kernel/src/Exports/Property.cpp
index 7a4610f42fbb7b8fa6414137f8edc874e5e845e0..1b437645aff69e87b5c817b331785cfba64d876a 100644
--- a/Framework/PythonInterface/mantid/kernel/src/Exports/Property.cpp
+++ b/Framework/PythonInterface/mantid/kernel/src/Exports/Property.cpp
@@ -24,20 +24,18 @@ using Mantid::PythonInterface::std_vector_exporter;
 using namespace boost::python;
 
 GET_POINTER_SPECIALIZATION(Property)
-// clang-format off
-DIAG_OFF(unknown-pragmas)
-DIAG_OFF(unused-local-typdef)
+DIAG_OFF("unknown-pragmas")
+DIAG_OFF("unused-local-typdef")
 // Ignore -Wconversion warnings coming from boost::python
 // Seen with GCC 7.1.1 and Boost 1.63.0
-DIAG_OFF(conversion)
-// clang-format on
+DIAG_OFF("conversion")
+
 BOOST_PYTHON_MEMBER_FUNCTION_OVERLOADS(valueAsPrettyStrOverloader,
+
                                        valueAsPrettyStr, 0, 2)
-// clang-format off
-DIAG_ON(conversion)
-DIAG_ON(unknown-pragmas)
-DIAG_ON(unused-local-typdef)
-// clang-format on
+DIAG_ON("conversion")
+DIAG_ON("unknown-pragmas")
+DIAG_ON("unused-local-typdef")
 
 void export_Property() {
   register_ptr_to_python<Property *>();
diff --git a/Framework/PythonInterface/mantid/kernel/src/Exports/Statistics.cpp b/Framework/PythonInterface/mantid/kernel/src/Exports/Statistics.cpp
index 7af14bf7efe04291d581adcb78a70aa12089a48e..8ae19f436b876f8d75fd0a6ebc47a56617f96342 100644
--- a/Framework/PythonInterface/mantid/kernel/src/Exports/Statistics.cpp
+++ b/Framework/PythonInterface/mantid/kernel/src/Exports/Statistics.cpp
@@ -97,21 +97,18 @@ Statistics getStatisticsNumpy(const NumPy::NdArray &data,
   }
 }
 
-// clang-format off
-DIAG_OFF(unknown-pragmas)
-DIAG_OFF(unused-local-typdef)
+DIAG_OFF("unknown-pragmas")
+DIAG_OFF("unused-local-typdef")
 // Ignore -Wconversion warnings coming from boost::python
 // Seen with GCC 7.1.1 and Boost 1.63.0
-DIAG_OFF(conversion)
-// clang-format on
+DIAG_OFF("conversion")
+
 // Define an overload to handle the default argument
 BOOST_PYTHON_FUNCTION_OVERLOADS(getStatisticsOverloads, getStatisticsNumpy, 1,
                                 2)
-// clang-format off
-DIAG_ON(conversion)
-DIAG_ON(unknown-pragmas)
-DIAG_ON(unused-local-typdef)
-// clang-format on
+DIAG_ON("conversion")
+DIAG_ON("unknown-pragmas")
+DIAG_ON("unused-local-typdef")
 //============================ Z score
 //============================================
 
@@ -160,21 +157,18 @@ std::vector<double> getModifiedZscoreNumpy(const NumPy::NdArray &data,
   }
 }
 
-// clang-format off
-DIAG_OFF(unknown-pragmas)
-DIAG_OFF(unused-local-typdef)
+DIAG_OFF("unknown-pragmas")
+DIAG_OFF("unused-local-typdef")
 // Ignore -Wconversion warnings coming from boost::python
 // Seen with GCC 7.1.1 and Boost 1.63.0
-DIAG_OFF(conversion)
-// clang-format on
+DIAG_OFF("conversion")
+
 // Define an overload to handle the default argument
 BOOST_PYTHON_FUNCTION_OVERLOADS(getModifiedZscoreOverloads,
                                 getModifiedZscoreNumpy, 1, 2)
-// clang-format off
-DIAG_ON(conversion)
-DIAG_ON(unknown-pragmas)
-DIAG_ON(unused-local-typdef)
-// clang-format on
+DIAG_ON("conversion")
+DIAG_ON("unknown-pragmas")
+DIAG_ON("unused-local-typdef")
 
 //============================ getMoments
 //============================================
@@ -225,21 +219,17 @@ std::vector<double> getMomentsAboutOriginNumpy(const NumPy::NdArray &indep,
   return getMomentsNumpyImpl(&getMomentsAboutOrigin, indep, depend, maxMoment);
 }
 
-// clang-format off
-DIAG_OFF(unknown-pragmas)
-DIAG_OFF(unused-local-typdef)
+DIAG_OFF("unknown-pragmas")
+DIAG_OFF("unused-local-typdef")
 // Ignore -Wconversion warnings coming from boost::python
 // Seen with GCC 7.1.1 and Boost 1.63.0
-DIAG_OFF(conversion)
-// clang-format on
+DIAG_OFF("conversion")
 // Define an overload to handle the default argument
 BOOST_PYTHON_FUNCTION_OVERLOADS(getMomentsAboutOriginOverloads,
                                 getMomentsAboutOriginNumpy, 2, 3)
-// clang-format off
-DIAG_ON(conversion)
-DIAG_ON(unknown-pragmas)
-DIAG_ON(unused-local-typdef)
-// clang-format on
+DIAG_ON("conversion")
+DIAG_ON("unknown-pragmas")
+DIAG_ON("unused-local-typdef")
 /**
  * Proxy for @see Mantid::Kernel::getMomentsAboutMean so that it can accept
  * numpy arrays
@@ -251,21 +241,17 @@ std::vector<double> getMomentsAboutMeanNumpy(const NumPy::NdArray &indep,
   return getMomentsNumpyImpl(&getMomentsAboutMean, indep, depend, maxMoment);
 }
 
-// clang-format off
-DIAG_OFF(unknown-pragmas)
-DIAG_OFF(unused-local-typdef)
+DIAG_OFF("unknown-pragmas")
+DIAG_OFF("unused-local-typdef")
 // Ignore -Wconversion warnings coming from boost::python
 // Seen with GCC 7.1.1 and Boost 1.63.0
-DIAG_OFF(conversion)
-// clang-format on
+DIAG_OFF("conversion")
 // Define an overload to handle the default argument
 BOOST_PYTHON_FUNCTION_OVERLOADS(getMomentsAboutMeanOverloads,
                                 getMomentsAboutMeanNumpy, 2, 3)
-// clang-format off
-DIAG_ON(conversion)
-DIAG_ON(unknown-pragmas)
-DIAG_ON(unused-local-typdef)
-// clang-format on
+DIAG_ON("conversion")
+DIAG_ON("unknown-pragmas")
+DIAG_ON("unused-local-typdef")
 
 ///@endcond
 }
diff --git a/Framework/PythonInterface/mantid/kernel/src/Registry/PropertyWithValueFactory.cpp b/Framework/PythonInterface/mantid/kernel/src/Registry/PropertyWithValueFactory.cpp
index 052bbebb7b98050e16904afee24f87536ec05f2a..0082d0e6d5e7184c56a5ef6d7e852f869cd8142e 100644
--- a/Framework/PythonInterface/mantid/kernel/src/Registry/PropertyWithValueFactory.cpp
+++ b/Framework/PythonInterface/mantid/kernel/src/Registry/PropertyWithValueFactory.cpp
@@ -187,9 +187,7 @@ const std::string PropertyWithValueFactory::isArray(PyObject *const object) {
 
     PyObject *item = PySequence_Fast_GET_ITEM(object, 0);
     // Boolean can be cast to int, so check first.
-    // clang-format off
-    DIAG_OFF(parentheses-equality)
-    // clang-format on
+    DIAG_OFF("parentheses-equality")
     if (PyBool_Check(item)) {
       throw std::runtime_error(
           "Unable to support extracting arrays of booleans.");
@@ -197,9 +195,7 @@ const std::string PropertyWithValueFactory::isArray(PyObject *const object) {
     if (PyLong_Check(item)) {
       return std::string("LongIntArray");
     }
-    // clang-format off
-    DIAG_ON(parentheses-equality)
-// clang-format on
+    DIAG_ON("parentheses-equality")
 
 #if PY_MAJOR_VERSION < 3
     // In python 2 ints & longs are separate
diff --git a/Framework/PythonInterface/test/testhelpers/WorkspaceCreationHelperModule.cpp b/Framework/PythonInterface/test/testhelpers/WorkspaceCreationHelperModule.cpp
index 36f88528d0785abf902925d3f8fc847793fc8a6d..d75a8ad43c7ddabdd087230d053ca34b1db6e189 100644
--- a/Framework/PythonInterface/test/testhelpers/WorkspaceCreationHelperModule.cpp
+++ b/Framework/PythonInterface/test/testhelpers/WorkspaceCreationHelperModule.cpp
@@ -22,13 +22,11 @@ using namespace Mantid::DataObjects::MDEventsTestHelper;
 using namespace Mantid::PythonInterface::Policies;
 using namespace WorkspaceCreationHelper;
 
-// clang-format off
-DIAG_OFF(unknown-pragmas)
-DIAG_OFF(unused-local-typdef)
+DIAG_OFF("unknown-pragmas")
+DIAG_OFF("unused-local-typdef")
 // Ignore -Wconversion warnings coming from boost::python
 // Seen with GCC 7.1.1 and Boost 1.63.0
-DIAG_OFF(conversion)
-// clang-format on
+DIAG_OFF("conversion")
 BOOST_PYTHON_FUNCTION_OVERLOADS(create2DWorkspaceWithFullInstrument_overloads,
                                 create2DWorkspaceWithFullInstrument, 2, 4)
 
@@ -38,11 +36,9 @@ BOOST_PYTHON_FUNCTION_OVERLOADS(makeFakeMDHistoWorkspace_overloads,
 BOOST_PYTHON_FUNCTION_OVERLOADS(
     create2DWorkspaceWithRectangularInstrument_overloads,
     create2DWorkspaceWithRectangularInstrument, 3, 3)
-// clang-format off
-DIAG_ON(conversion)
-DIAG_ON(unknown-pragmas)
-DIAG_ON(unused-local-typdef)
-// clang-format on
+DIAG_ON("conversion")
+DIAG_ON("unknown-pragmas")
+DIAG_ON("unused-local-typdef")
 
 BOOST_PYTHON_MODULE(WorkspaceCreationHelper) {
   using namespace boost::python;
diff --git a/MantidPlot/src/PythonScript.cpp b/MantidPlot/src/PythonScript.cpp
index c7bf3395d61935dafada314b2f018c8846a49be7..0945360aa710ee33d8ee5a718c5de88b13e0a2e2 100644
--- a/MantidPlot/src/PythonScript.cpp
+++ b/MantidPlot/src/PythonScript.cpp
@@ -540,13 +540,9 @@ QVariant PythonScript::evaluateImpl() {
     }
   }
   /* bool */
-  // clang-format off
-  DIAG_OFF(parentheses-equality)
-  // clang-format on
+  DIAG_OFF("parentheses-equality")
   else if (PyBool_Check(pyret)) {
-    // clang-format off
-  DIAG_ON(parentheses-equality)
-    // clang-format on
+  DIAG_ON("parentheses-equality")
     qret = QVariant(pyret == Py_True);
   }
   // could handle advanced types (such as PyList->QValueList) here if needed
diff --git a/qt/paraview_ext/PVPlugins/Sources/MDEWSource/vtkMDEWSource.cxx b/qt/paraview_ext/PVPlugins/Sources/MDEWSource/vtkMDEWSource.cxx
index 4ec4bf724db06995eef02e8ac6464bfd6e99c118..1e3234c2604e544d14f438bff732ad172a6f331c 100644
--- a/qt/paraview_ext/PVPlugins/Sources/MDEWSource/vtkMDEWSource.cxx
+++ b/qt/paraview_ext/PVPlugins/Sources/MDEWSource/vtkMDEWSource.cxx
@@ -185,9 +185,7 @@ int vtkMDEWSource::RequestData(vtkInformation *, vtkInformationVector **,
   return 1;
 }
 
-// clang-format off
-DIAG_OFF(strict-aliasing)
-// clang-format on
+DIAG_OFF("strict-aliasing")
 int vtkMDEWSource::RequestInformation(
     vtkInformation *vtkNotUsed(request),
     vtkInformationVector **vtkNotUsed(inputVector),
diff --git a/qt/paraview_ext/VatesAPI/src/vtkDataSetToPeaksFilteredDataSet.cpp b/qt/paraview_ext/VatesAPI/src/vtkDataSetToPeaksFilteredDataSet.cpp
index 4999cbb5ebc29f23b0700ecde9fe3e6324fbd310..4e57eac73c6866796a1ee95174182dd6efdb59d2 100644
--- a/qt/paraview_ext/VatesAPI/src/vtkDataSetToPeaksFilteredDataSet.cpp
+++ b/qt/paraview_ext/VatesAPI/src/vtkDataSetToPeaksFilteredDataSet.cpp
@@ -176,9 +176,7 @@ vtkDataSetToPeaksFilteredDataSet::getPeaksInfo(
   return peaksInfo;
 }
 
-// clang-format off
-DIAG_OFF(strict-aliasing)
-// clang-format on
+DIAG_OFF("strict-aliasing")
 /**
  * Get the radius from a PeakShape object.
  * @param shape The PeakShape from which the information will be extracted.
diff --git a/qt/paraview_ext/VatesAPI/test/BoxInfoTest.h b/qt/paraview_ext/VatesAPI/test/BoxInfoTest.h
index 77b42a294456de564ea846f18572926bc2110152..553947445fe8e6c50463e1df81cf1fe6eee9548b 100644
--- a/qt/paraview_ext/VatesAPI/test/BoxInfoTest.h
+++ b/qt/paraview_ext/VatesAPI/test/BoxInfoTest.h
@@ -54,9 +54,7 @@ public:
     AnalysisDataService::Instance().remove(wsName);
   }
 
-  // clang-format off
-  DIAG_OFF(strict-aliasing)
-  // clang-format on
+  DIAG_OFF("strict-aliasing")
   void test_initial_recursion_depth_is_1_for_MD_Event_w_split() {
     // Arrange
     const std::string wsName = "MD_EVENT_WS_WITH_SPLITTING";
diff --git a/qt/paraview_ext/VatesSimpleGui/ViewWidgets/src/ViewBase.cpp b/qt/paraview_ext/VatesSimpleGui/ViewWidgets/src/ViewBase.cpp
index 874f9077522b66a39db4617c11e9fac2b7275baf..e16cf8128fdcadfec24f2025c34795f9df09358c 100644
--- a/qt/paraview_ext/VatesSimpleGui/ViewWidgets/src/ViewBase.cpp
+++ b/qt/paraview_ext/VatesSimpleGui/ViewWidgets/src/ViewBase.cpp
@@ -268,9 +268,7 @@ pqPipelineRepresentation *ViewBase::getPvActiveRep() {
   return qobject_cast<pqPipelineRepresentation *>(drep);
 }
 
-// clang-format off
-DIAG_OFF(strict-aliasing)
-// clang-format on
+DIAG_OFF("strict-aliasing")
 /**
  * This function creates a ParaView source from a given plugin name and
  * workspace name. This is used in the plugin mode of the simple interface.