(feat) support for diagnostic tags (#543)

Author: jasonlyu123

packages/language-server/src/plugins/typescript/features/DiagnosticsProvider.ts

@@ -1,5 +1,5 @@
 import ts from 'typescript';
-import { Diagnostic, DiagnosticSeverity } from 'vscode-languageserver';
+import { Diagnostic, DiagnosticSeverity, DiagnosticTag } from 'vscode-languageserver';
 import { Document, mapObjWithRangeToOriginal, getTextInRange } from '../../../lib/documents';
 import { DiagnosticsProvider } from '../../interfaces';
 import { LSAndTSDocResolver } from '../LSAndTSDocResolver';
@@ -35,19 +35,31 @@ export class DiagnosticsProviderImpl implements DiagnosticsProvider {
         const fragment = await tsDoc.getFragment();
 
         return diagnostics
-            .map((diagnostic) => ({
+            .map<Diagnostic>((diagnostic) => ({
                 range: convertRange(tsDoc, diagnostic),
                 severity: mapSeverity(diagnostic.category),
                 source: isTypescript ? 'ts' : 'js',
                 message: ts.flattenDiagnosticMessageText(diagnostic.messageText, '\n'),
                 code: diagnostic.code,
+                tags: this.getDiagnosticTag(diagnostic)
             }))
             .map((diagnostic) => mapObjWithRangeToOriginal(fragment, diagnostic))
             .filter(hasNoNegativeLines)
             .filter(isNoFalsePositive(document.getText(), tsDoc))
             .map(enhanceIfNecessary);
     }
 
+    private getDiagnosticTag(diagnostic: ts.Diagnostic) {
+        const tags: DiagnosticTag[] = [];
+        if (diagnostic.reportsUnnecessary) {
+            tags.push(DiagnosticTag.Unnecessary);
+        }
+        if (diagnostic.reportsDeprecated) {
+            tags.push(DiagnosticTag.Deprecated);
+        }
+        return tags;
+    }
+
     private getLSAndTSDoc(document: Document) {
         return this.lsAndTsDocResolver.getLSAndTSDoc(document);
     }

packages/language-server/test/plugins/typescript/features/DiagnosticsProvider.test.ts

@@ -38,6 +38,7 @@ describe('DiagnosticsProvider', () => {
                 },
                 severity: 1,
                 source: 'ts',
+                tags: [],
             },
         ]);
     });
@@ -62,6 +63,7 @@ describe('DiagnosticsProvider', () => {
                 },
                 severity: 1,
                 source: 'js',
+                tags: [],
             },
         ]);
     });
@@ -109,4 +111,46 @@ describe('DiagnosticsProvider', () => {
         const diagnostics = await plugin.getDiagnostics(document);
         assert.deepStrictEqual(diagnostics, []);
     });
+
+    it('provide diagnostics tags', async () => {
+        const { plugin, document } = setup('diagnostics-tag.svelte');
+        const diagnostics = await plugin.getDiagnostics(document);
+
+        assert.deepStrictEqual(diagnostics, [
+            {
+                code: 6385,
+                message: "'a' is deprecated",
+                range: {
+                    end: {
+                        character: 5,
+                        line: 3,
+                    },
+                    start: {
+                        character: 4,
+                        line: 3,
+                    },
+                },
+                severity: 4,
+                source: 'ts',
+                tags: [2],
+            },
+            {
+                code: 6133,
+                message: "'c' is declared but its value is never read.",
+                range: {
+                    end: {
+                        character: 9,
+                        line: 4,
+                    },
+                    start: {
+                        character: 8,
+                        line: 4,
+                    },
+                },
+                severity: 4,
+                source: 'ts',
+                tags: [1],
+            },
+        ]);
+    });
 });

packages/language-server/test/plugins/typescript/testfiles/diagnostics-tag.svelte

@@ -0,0 +1,6 @@
+<script lang="ts">
+    /**@deprecated*/
+    let a;
+    a;
+    let c;
+</script>