[wasm][debugger]Add hidden attribute support (#61143)

* Draft of hidden attribute decorator use.

* Removed checking custom attributes in the runtime each time the breakpoint is set and moved it to the constructor which is more efficient.

* Added test for DebuggerHidden decorator.

* By adding a line: using System.Diagnostics; IntAdd method moved down one line what resulted in CreateGoodBreakpoint tests failures. All row numbers in these tests had to be incremented.

* Reverted edition of tests not connected with HiddenAttribute.

* Added visible method to the HiddenAttribute test.

* Applying thaystg review suggestion.

src/mono/wasm/debugger/BrowserDebugProxy/DebugStore.cs

@@ -330,6 +330,7 @@ internal class MethodInfo
         internal LocalScopeHandleCollection localScopes;
         public bool IsStatic() => (methodDef.Attributes & MethodAttributes.Static) != 0;
         public int IsAsync { get; set; }
+        public bool IsHiddenFromDebugger { get; }
         public MethodInfo(AssemblyInfo assembly, MethodDefinitionHandle methodDefHandle, int token, SourceFile source, TypeInfo type, MetadataReader asmMetadataReader, MetadataReader pdbMetadataReader)
         {
             this.IsAsync = -1;
@@ -363,6 +364,18 @@ public MethodInfo(AssemblyInfo assembly, MethodDefinitionHandle methodDefHandle,
 
                 StartLocation = new SourceLocation(this, start);
                 EndLocation = new SourceLocation(this, end);
+
+                foreach (var cattr in methodDef.GetCustomAttributes())
+                {
+                    var ctorHandle = asmMetadataReader.GetCustomAttribute(cattr).Constructor;
+                    if (ctorHandle.Kind == HandleKind.MemberReference)
+                    {
+                        var container = asmMetadataReader.GetMemberReference((MemberReferenceHandle)ctorHandle).Parent;
+                        var name = asmMetadataReader.GetString(asmMetadataReader.GetTypeReference((TypeReferenceHandle)container).Name);
+                        if (name == "DebuggerHiddenAttribute")
+                            this.IsHiddenFromDebugger = true;
+                    }
+                }
             }
             localScopes = pdbMetadataReader.GetLocalScopes(methodDefHandle);
         }

src/mono/wasm/debugger/BrowserDebugProxy/MonoProxy.cs

@@ -1301,6 +1301,9 @@ private async Task SetBreakpoint(SessionId sessionId, DebugStore store, Breakpoi
             {
                 SourceLocation loc = sourceId.First();
                 req.Method = loc.CliLocation.Method;
+                if (req.Method.IsHiddenFromDebugger)
+                    continue;
+
                 Breakpoint bp = await SetMonoBreakpoint(sessionId, req.Id, loc, req.Condition, token);
 
                 // If we didn't successfully enable the breakpoint

src/mono/wasm/debugger/DebuggerTestSuite/BreakpointTests.cs

@@ -642,5 +642,21 @@ await EvaluateAndCheck(
                 }
             );
         }
+
+
+        [Fact]
+        public async Task DebuggerAttributeNoStopInDebuggerHidden()
+        {
+            var bp_hidden = await SetBreakpointInMethod("debugger-test.dll", "DebuggerAttribute", "HiddenMethod", 1);
+            var bp_visible = await SetBreakpointInMethod("debugger-test.dll", "DebuggerAttribute", "VisibleMethod", 1);
+            Assert.Empty(bp_hidden.Value["locations"]);
+            await EvaluateAndCheck(
+                "window.setTimeout(function() { invoke_static_method('[debugger-test] DebuggerAttribute:VisibleMethod'); }, 1);",
+                "dotnet://debugger-test.dll/debugger-test.cs",
+                bp_visible.Value["locations"][0]["lineNumber"].Value<int>(),
+                bp_visible.Value["locations"][0]["columnNumber"].Value<int>(),
+                "VisibleMethod"
+            );
+        }
     }
 }

src/mono/wasm/debugger/tests/debugger-test/debugger-test.cs

@@ -807,3 +807,25 @@ public int Increment(int count)
         return count + 1;
     }
 }
+
+public class DebuggerAttribute
+{
+    static int currentCount = 0;
+
+    [System.Diagnostics.DebuggerHidden]
+    public static void HiddenMethod()
+    {
+        currentCount++;
+    }
+
+    public static void VisibleMethod()
+    {
+        currentCount++;
+    }
+
+    public static void Run()
+    {
+        HiddenMethod();
+        VisibleMethod();
+    }
+}