Display IEnumerables and IDictionaries in debugger prettily (with "Raw View" available) (#1634)

JustinGrote · SeeminglyScience · andyleejordan · web-flow · commit 3ea4eb97e641 · 2022-01-24T20:41:40.000Z
This takes inspiration from the C# extension to display enumerables and dictionaries
in a human-friendly and "pretty" manner in the debugger. For advanced debugging,
the "Raw View" is available under a pseudo-variable of the same name.

Co-authored-by: Patrick Meinecke &lt;SeeminglyScience@users.noreply.github.com&gt;
Co-authored-by: Andy Schwartzmeyer &lt;andrew@schwartzmeyer.com&gt;
diff --git a/src/PowerShellEditorServices/Services/DebugAdapter/Debugging/VariableDetails.cs b/src/PowerShellEditorServices/Services/DebugAdapter/Debugging/VariableDetails.cs
@@ -26,8 +26,7 @@ internal class VariableDetails : VariableDetailsBase
         /// Provides a constant for the dollar sign variable prefix string.
         /// </summary>
         public const string DollarPrefix = "$";
-
-        private object valueObject;
+        protected object ValueObject { get; }
         private VariableDetails[] cachedChildren;
 
         #endregion
@@ -81,7 +80,7 @@ public VariableDetails(PSPropertyInfo psProperty)
         /// <param name="value">The variable's value.</param>
         public VariableDetails(string name, object value)
         {
-            this.valueObject = value;
+            this.ValueObject = value;
 
             this.Id = -1; // Not been assigned a variable reference id yet
             this.Name = name;
@@ -109,7 +108,7 @@ public override VariableDetailsBase[] GetChildren(ILogger logger)
             {
                 if (this.cachedChildren == null)
                 {
-                    this.cachedChildren = GetChildren(this.valueObject, logger);
+                    this.cachedChildren = GetChildren(this.ValueObject, logger);
                 }
 
                 return this.cachedChildren;
@@ -175,19 +174,18 @@ private static string GetValueStringAndType(object value, bool isExpandable, out
             if (value is bool)
             {
                 // Set to identifier recognized by PowerShell to make setVariable from the debug UI more natural.
-                valueString = (bool) value ? "$true" : "$false";
+                valueString = (bool)value ? "$true" : "$false";
 
                 // We need to use this "magic value" to highlight in vscode properly
                 // These "magic values" are analagous to TypeScript and are visible in VSCode here:
                 // https://github.com/microsoft/vscode/blob/57ca9b99d5b6a59f2d2e0f082ae186559f45f1d8/src/vs/workbench/contrib/debug/browser/baseDebugView.ts#L68-L78
-                // NOTE: we don't do numbers and strings since they (so far) seem to get detected properly by 
-                //serialization, and the original .NET type can be preserved so it shows up in the variable name 
-                //type hover as the original .NET type.
+                // NOTE: we don't do numbers and strings since they (so far) seem to get detected properly by
+                // serialization, and the original .NET type can be preserved so it shows up in the variable name
+                // type hover as the original .NET type.
                 typeName = "boolean";
             }
             else if (isExpandable)
             {
-
                 // Get the "value" for an expandable object.
                 if (value is DictionaryEntry)
                 {
@@ -367,12 +365,19 @@ private VariableDetails[] GetChildren(object obj, ILogger logger)
             return childVariables.ToArray();
         }
 
-        private static void AddDotNetProperties(object obj, List<VariableDetails> childVariables)
+        protected static void AddDotNetProperties(object obj, List<VariableDetails> childVariables, bool noRawView = false)
         {
             Type objectType = obj.GetType();
-            var properties =
-                objectType.GetProperties(
-                    BindingFlags.Public | BindingFlags.Instance);
+
+            // For certain array or dictionary types, we want to hide additional properties under a "raw view" header
+            // to reduce noise. This is inspired by the C# vscode extension.
+            if (!noRawView && obj is IEnumerable)
+            {
+                childVariables.Add(new VariableDetailsRawView(obj));
+                return;
+            }
+
+            var properties = objectType.GetProperties(BindingFlags.Public | BindingFlags.Instance);
 
             foreach (var property in properties)
             {
@@ -424,4 +429,25 @@ public override string ToString()
             }
         }
     }
+
+    /// <summary>
+    /// A VariableDetails that only returns the raw view properties of the object, rather than its values.
+    /// </summary>
+    internal sealed class VariableDetailsRawView : VariableDetails
+    {
+        private const string RawViewName = "Raw View";
+
+        public VariableDetailsRawView(object value) : base(RawViewName, value)
+        {
+            this.ValueString = "";
+            this.Type = "";
+        }
+
+        public override VariableDetailsBase[] GetChildren(ILogger logger)
+        {
+            List<VariableDetails> childVariables = new();
+            AddDotNetProperties(ValueObject, childVariables, noRawView: true);
+            return childVariables.ToArray();
+        }
+    }
 }
diff --git a/test/PowerShellEditorServices.Test.Shared/Debugging/VariableTest.ps1 b/test/PowerShellEditorServices.Test.Shared/Debugging/VariableTest.ps1
@@ -24,3 +24,30 @@ function Test-Variables {
 Test-Variables
 # NOTE: If a line is added to the function above, the line numbers in the
 # associated unit tests MUST be adjusted accordingly.
+
+$SCRIPT:simpleArray = @(
+    1
+    2
+    'red'
+    'blue'
+)
+
+# This is a dummy function that the test will use to stop and evaluate the debug environment
+function __BreakDebuggerEnumerableShowsRawView{}; __BreakDebuggerEnumerableShowsRawView
+
+$SCRIPT:simpleDictionary = @{
+    item1 = 1
+    item2 = 2
+    item3 = 'red'
+    item4 = 'blue'
+}
+function __BreakDebuggerDictionaryShowsRawView{}; __BreakDebuggerDictionaryShowsRawView
+
+$SCRIPT:sortedDictionary = [Collections.Generic.SortedDictionary[string, object]]::new()
+$sortedDictionary[1] = 1
+$sortedDictionary[2] = 2
+$sortedDictionary['red'] = 'red'
+$sortedDictionary['blue'] = 'red'
+
+# This is a dummy function that the test will use to stop and evaluate the debug environment
+function __BreakDebuggerDerivedDictionaryPropertyInRawView{}; __BreakDebuggerDerivedDictionaryPropertyInRawView
diff --git a/test/PowerShellEditorServices.Test/Debugging/DebugServiceTests.cs b/test/PowerShellEditorServices.Test/Debugging/DebugServiceTests.cs
@@ -112,7 +112,8 @@ private void AssertDebuggerPaused()
 
         private void AssertDebuggerStopped(
             string scriptPath = "",
-            int lineNumber = -1)
+            int lineNumber = -1,
+            CommandBreakpointDetails commandBreakpointDetails = default)
         {
             var eventArgs = debuggerStoppedQueue.Take(new CancellationTokenSource(5000).Token);
 
@@ -132,6 +133,11 @@ private void AssertDebuggerStopped(
             {
                 Assert.Equal(lineNumber, eventArgs.LineNumber);
             }
+
+            if (commandBreakpointDetails is not null)
+            {
+                Assert.Equal(commandBreakpointDetails.Name, eventArgs.OriginalEvent.InvocationInfo.MyCommand.Name);
+            }
         }
 
         private Task<IReadOnlyList<LineBreakpoint>> GetConfirmedBreakpoints(ScriptFile scriptFile)
@@ -210,7 +216,8 @@ public async Task DebuggerAcceptsScriptArgs()
             Assert.True(var.IsExpandable);
 
             var childVars = debugService.GetVariables(var.Id);
-            Assert.Equal(9, childVars.Length);
+            // 2 variables plus "Raw View"
+            Assert.Equal(3, childVars.Length);
             Assert.Equal("\"Bar\"", childVars[0].ValueString);
             Assert.Equal("\"Baz\"", childVars[1].ValueString);
 
@@ -227,7 +234,7 @@ public async Task DebuggerAcceptsScriptArgs()
             Assert.True(var.IsExpandable);
 
             childVars = debugService.GetVariables(var.Id);
-            Assert.Equal(8, childVars.Length);
+            Assert.Equal(2, childVars.Length);
             Assert.Equal("\"Extra1\"", childVars[0].ValueString);
         }
 
@@ -532,14 +539,15 @@ await debugService.SetLineBreakpointsAsync(
             Assert.True(objVar.IsExpandable);
 
             var objChildren = debugService.GetVariables(objVar.Id);
-            Assert.Equal(9, objChildren.Length);
+            // Two variables plus "Raw View"
+            Assert.Equal(3, objChildren.Length);
 
             var arrVar = Array.Find(variables, v => v.Name == "$arrVar");
             Assert.NotNull(arrVar);
             Assert.True(arrVar.IsExpandable);
 
             var arrChildren = debugService.GetVariables(arrVar.Id);
-            Assert.Equal(11, arrChildren.Length);
+            Assert.Equal(5, arrChildren.Length);
 
             var classVar = Array.Find(variables, v => v.Name == "$classVar");
             Assert.NotNull(classVar);
@@ -709,7 +717,8 @@ await debugService.SetLineBreakpointsAsync(
             Assert.True(var.IsExpandable);
 
             VariableDetailsBase[] childVars = debugService.GetVariables(var.Id);
-            Assert.Equal(9, childVars.Length);
+            // 2 variables plus "Raw View"
+            Assert.Equal(3, childVars.Length);
             Assert.Equal("[0]", childVars[0].Name);
             Assert.Equal("[1]", childVars[1].Name);
 
@@ -772,6 +781,107 @@ await debugService.SetLineBreakpointsAsync(
             Assert.Equal("\"John\"", childVars["Name"]);
         }
 
+        [Fact]
+        public async Task DebuggerEnumerableShowsRawView()
+        {
+            CommandBreakpointDetails breakpoint = CommandBreakpointDetails.Create("__BreakDebuggerEnumerableShowsRawView");
+            await debugService.SetCommandBreakpointsAsync(new[] { breakpoint }).ConfigureAwait(true);
+
+            // Execute the script and wait for the breakpoint to be hit
+            Task _ = ExecuteVariableScriptFile();
+            AssertDebuggerStopped(commandBreakpointDetails: breakpoint);
+
+            VariableDetailsBase simpleArrayVar = Array.Find(
+                GetVariables(VariableContainerDetails.ScriptScopeName),
+                v => v.Name == "$simpleArray");
+            Assert.NotNull(simpleArrayVar);
+            VariableDetailsBase rawDetailsView = Array.Find(
+                simpleArrayVar.GetChildren(NullLogger.Instance),
+                v => v.Name == "Raw View");
+            Assert.NotNull(rawDetailsView);
+            Assert.Empty(rawDetailsView.Type);
+            Assert.Empty(rawDetailsView.ValueString);
+            VariableDetailsBase[] rawViewChildren = rawDetailsView.GetChildren(NullLogger.Instance);
+            Assert.Equal(7, rawViewChildren.Length);
+            Assert.Equal("Length", rawViewChildren[0].Name);
+            Assert.Equal("4", rawViewChildren[0].ValueString);
+            Assert.Equal("LongLength", rawViewChildren[1].Name);
+            Assert.Equal("4", rawViewChildren[1].ValueString);
+            Assert.Equal("Rank", rawViewChildren[2].Name);
+            Assert.Equal("1", rawViewChildren[2].ValueString);
+            Assert.Equal("SyncRoot", rawViewChildren[3].Name);
+            Assert.Equal("IsReadOnly", rawViewChildren[4].Name);
+            Assert.Equal("$false", rawViewChildren[4].ValueString);
+            Assert.Equal("IsFixedSize", rawViewChildren[5].Name);
+            Assert.Equal("$true", rawViewChildren[5].ValueString);
+            Assert.Equal("IsSynchronized", rawViewChildren[6].Name);
+            Assert.Equal("$false", rawViewChildren[6].ValueString);
+        }
+
+        [Fact]
+        public async Task DebuggerDictionaryShowsRawView()
+        {
+            CommandBreakpointDetails breakpoint = CommandBreakpointDetails.Create("__BreakDebuggerDictionaryShowsRawView");
+            await debugService.SetCommandBreakpointsAsync(new[] { breakpoint }).ConfigureAwait(true);
+
+            // Execute the script and wait for the breakpoint to be hit
+            Task _ = ExecuteVariableScriptFile();
+            AssertDebuggerStopped(commandBreakpointDetails: breakpoint);
+
+            VariableDetailsBase simpleDictionaryVar = Array.Find(
+                GetVariables(VariableContainerDetails.ScriptScopeName),
+                v => v.Name == "$simpleDictionary");
+            Assert.NotNull(simpleDictionaryVar);
+            VariableDetailsBase rawDetailsView = Array.Find(
+                simpleDictionaryVar.GetChildren(NullLogger.Instance),
+                v => v.Name == "Raw View");
+            Assert.NotNull(rawDetailsView);
+            Assert.Empty(rawDetailsView.Type);
+            Assert.Empty(rawDetailsView.ValueString);
+            VariableDetailsBase[] rawViewChildren = rawDetailsView.GetChildren(NullLogger.Instance);
+            Assert.Equal(7, rawViewChildren.Length);
+            Assert.Equal("IsReadOnly", rawViewChildren[0].Name);
+            Assert.Equal("$false", rawViewChildren[0].ValueString);
+            Assert.Equal("IsFixedSize", rawViewChildren[1].Name);
+            Assert.Equal("$false", rawViewChildren[1].ValueString);
+            Assert.Equal("IsSynchronized", rawViewChildren[2].Name);
+            Assert.Equal("$false", rawViewChildren[2].ValueString);
+            Assert.Equal("Keys", rawViewChildren[3].Name);
+            Assert.Equal("Values", rawViewChildren[4].Name);
+            Assert.Equal("[ValueCollection: 4]", rawViewChildren[4].ValueString);
+            Assert.Equal("SyncRoot", rawViewChildren[5].Name);
+            Assert.Equal("Count", rawViewChildren[6].Name);
+            Assert.Equal("4", rawViewChildren[6].ValueString);
+        }
+
+        [Fact]
+        public async Task DebuggerDerivedDictionaryPropertyInRawView()
+        {
+            CommandBreakpointDetails breakpoint = CommandBreakpointDetails.Create("__BreakDebuggerDerivedDictionaryPropertyInRawView");
+            await debugService.SetCommandBreakpointsAsync(new[] { breakpoint }).ConfigureAwait(true);
+
+            // Execute the script and wait for the breakpoint to be hit
+            Task _ = ExecuteVariableScriptFile();
+            AssertDebuggerStopped(commandBreakpointDetails: breakpoint);
+
+            VariableDetailsBase sortedDictionaryVar = Array.Find(
+                GetVariables(VariableContainerDetails.ScriptScopeName),
+                v => v.Name == "$sortedDictionary");
+            Assert.NotNull(sortedDictionaryVar);
+            VariableDetailsBase[] simpleDictionaryChildren = sortedDictionaryVar.GetChildren(NullLogger.Instance);
+            // 4 items + Raw View
+            Assert.Equal(5, simpleDictionaryChildren.Length);
+            VariableDetailsBase rawDetailsView = Array.Find(
+                simpleDictionaryChildren,
+                v => v.Name == "Raw View");
+            Assert.NotNull(rawDetailsView);
+            Assert.Empty(rawDetailsView.Type);
+            Assert.Empty(rawDetailsView.ValueString);
+            VariableDetailsBase[] rawViewChildren = rawDetailsView.GetChildren(NullLogger.Instance);
+            Assert.Equal(4, rawViewChildren.Length);
+            Assert.NotNull(Array.Find(rawViewChildren, v => v .Name == "Comparer"));
+        }
+
         [Fact]
         public async Task DebuggerVariablePSCustomObjectDisplaysCorrectly()
         {
