test to ensure diagnostics are logged

Author: nikalra

mlir/test/python/ir/diagnostic_handler.py

@@ -2,6 +2,7 @@
 
 import gc
 from mlir.ir import *
+from mlir._mlir_libs._mlirPythonTestNanobind import test_diagnostics_with_errors_and_notes
 
 
 def run(f):
@@ -222,3 +223,16 @@ def callback2(d):
     # CHECK: CALLBACK2: foobar
     # CHECK: CALLBACK1: foobar
     loc.emit_error("foobar")
+
+# CHECK-LABEL: TEST: testBuiltInDiagnosticsHandler
+@run
+def testBuiltInDiagnosticsHandler():
+    ctx = Context()
+
+    try:
+        test_diagnostics_with_errors_and_notes(ctx)
+    except ValueError as e:
+        # CHECK: created error
+        # CHECK: MLIRPythonCAPI
+        print(e)
+

mlir/test/python/lib/PythonTestModuleNanobind.cpp

@@ -11,9 +11,12 @@
 #include "PythonTestCAPI.h"
 #include "mlir-c/BuiltinAttributes.h"
 #include "mlir-c/BuiltinTypes.h"
+#include "mlir-c/Diagnostics.h"
 #include "mlir-c/IR.h"
+#include "mlir/Bindings/Python/Diagnostics.h"
 #include "mlir/Bindings/Python/Nanobind.h"
 #include "mlir/Bindings/Python/NanobindAdaptors.h"
+#include "nanobind/nanobind.h"
 
 namespace nb = nanobind;
 using namespace mlir::python::nanobind_adaptors;
@@ -45,6 +48,15 @@ NB_MODULE(_mlirPythonTestNanobind, m) {
       },
       nb::arg("registry"));
 
+  m.def("test_diagnostics_with_errors_and_notes", [](MlirContext ctx) {
+    mlirContextPrintStackTraceOnDiagnostic(ctx, true);
+    mlir::python::CollectDiagnosticsToStringScope handler(ctx);
+
+    auto loc = mlirLocationUnknownGet(ctx);
+    mlirEmitError(loc, "created error");
+    throw nb::value_error(handler.takeMessage().c_str());
+  });
+
   mlir_attribute_subclass(m, "TestAttr",
                           mlirAttributeIsAPythonTestTestAttribute,
                           mlirPythonTestTestAttributeGetTypeID)