2 files changed, 85 insertions, 2 deletions

diff --git a/editors/code/src/utils/rust_diagnostics.ts b/editors/code/src/utils/rust_diagnostics.ts
index ed049c95e..3c524cb37 100644
--- a/editors/code/src/utils/rust_diagnostics.ts
+++ b/editors/code/src/utils/rust_diagnostics.ts
@@ -187,8 +187,18 @@ export function mapRustDiagnosticToVsCode(
 
     const vd = new vscode.Diagnostic(location.range, rd.message, severity);
 
-    vd.source = 'rustc';
-    vd.code = rd.code ? rd.code.code : undefined;
+    let source = 'rustc';
+    let code = rd.code && rd.code.code;
+    if (code) {
+        // See if this is an RFC #2103 scoped lint (e.g. from Clippy)
+        const scopedCode = code.split('::');
+        if (scopedCode.length === 2) {
+            [source, code] = scopedCode;
+        }
+    }
+
+    vd.source = source;
+    vd.code = code;
     vd.relatedInformation = [];
 
     for (const secondarySpan of secondarySpans) {
diff --git a/editors/code/src/utils/vscode_diagnostics.ts b/editors/code/src/utils/vscode_diagnostics.ts
new file mode 100644
index 000000000..9d763c8d6
--- /dev/null
+++ b/editors/code/src/utils/vscode_diagnostics.ts
@@ -0,0 +1,73 @@
+import * as vscode from 'vscode';
+
+/** Compares two `vscode.Diagnostic`s for equality */
+export function areDiagnosticsEqual(
+    left: vscode.Diagnostic,
+    right: vscode.Diagnostic
+): boolean {
+    return (
+        left.source === right.source &&
+        left.severity === right.severity &&
+        left.range.isEqual(right.range) &&
+        left.message === right.message
+    );
+}
+
+/** Compares two `vscode.TextEdit`s for equality */
+function areTextEditsEqual(
+    left: vscode.TextEdit,
+    right: vscode.TextEdit
+): boolean {
+    if (!left.range.isEqual(right.range)) {
+        return false;
+    }
+
+    if (left.newText !== right.newText) {
+        return false;
+    }
+
+    return true;
+}
+
+/** Compares two `vscode.CodeAction`s for equality */
+export function areCodeActionsEqual(
+    left: vscode.CodeAction,
+    right: vscode.CodeAction
+): boolean {
+    if (
+        left.kind !== right.kind ||
+        left.title !== right.title ||
+        !left.edit ||
+        !right.edit
+    ) {
+        return false;
+    }
+
+    const leftEditEntries = left.edit.entries();
+    const rightEditEntries = right.edit.entries();
+
+    if (leftEditEntries.length !== rightEditEntries.length) {
+        return false;
+    }
+
+    for (let i = 0; i < leftEditEntries.length; i++) {
+        const [leftUri, leftEdits] = leftEditEntries[i];
+        const [rightUri, rightEdits] = rightEditEntries[i];
+
+        if (leftUri.toString() !== rightUri.toString()) {
+            return false;
+        }
+
+        if (leftEdits.length !== rightEdits.length) {
+            return false;
+        }
+
+        for (let j = 0; j < leftEdits.length; j++) {
+            if (!areTextEditsEqual(leftEdits[j], rightEdits[j])) {
+                return false;
+            }
+        }
+    }
+
+    return true;
+}