feat: #338 - Add Diagnostic.getLineNumber()

docs/setup/diagnostics.md

@@ -33,12 +33,13 @@ Source file the diagnostic occurs in:
 const sourceFile = diagnostic.getSourceFile(); // returns: SourceFile | undefined
 ```
 
-#### Start & length
+#### Start, line number, & length
 
-Position in the file and length of the diagnostic:
+Position in the file, the line number, and length of the diagnostic:
 
 ```ts
 const start = diagnostic.getStart();   // returns: number
+const lineNumber = diagnostic.getLineNumber();   // returns: number
 const length = diagnostic.getLength(); // returns: number
 ```
 

lib/ts-simple-ast.d.ts

@@ -8203,6 +8203,10 @@ export declare class Diagnostic<TCompilerObject extends ts.Diagnostic = ts.Diagn
      * Gets the message text.
      */
     getMessageText(): string | DiagnosticMessageChain;
+    /**
+     * Gets the line number.
+     */
+    getLineNumber(): number | undefined;
     /**
      * Gets the start.
      */
@@ -8226,6 +8230,10 @@ export declare class Diagnostic<TCompilerObject extends ts.Diagnostic = ts.Diagn
 }
 
 export declare class DiagnosticWithLocation extends Diagnostic<ts.DiagnosticWithLocation> {
+    /**
+     * Gets the line number.
+     */
+    getLineNumber(): number;
     /**
      * Gets the start.
      */

src/compiler/tools/results/Diagnostic.ts

@@ -49,6 +49,17 @@ export class Diagnostic<TCompilerObject extends ts.Diagnostic = ts.Diagnostic> {
             return this.global.compilerFactory.getDiagnosticMessageChain(messageText);
     }
 
+    /**
+     * Gets the line number.
+     */
+    getLineNumber() {
+        const sourceFile = this.getSourceFile();
+        const start = this.getStart();
+        if (sourceFile == null || start == null)
+            return undefined;
+        return sourceFile.getLineNumberFromPos(start);
+    }
+
     /**
      * Gets the start.
      */

src/compiler/tools/results/DiagnosticWithLocation.ts

@@ -8,6 +8,13 @@ export class DiagnosticWithLocation extends Diagnostic<ts.DiagnosticWithLocation
         super(global, compilerObject);
     }
 
+    /**
+     * Gets the line number.
+     */
+    getLineNumber() {
+        return super.getLineNumber()!;
+    }
+
     /**
      * Gets the start.
      */

src/tests/compiler/tools/diagnosticTests.ts

@@ -44,6 +44,12 @@ describe(nameof(Diagnostic), () => {
         });
     });
 
+    describe(nameof<Diagnostic>(d => d.getLineNumber), () => {
+        it("should get the line number", () => {
+            expect(constError.getLineNumber()).to.equal(1);
+        });
+    });
+
     describe(nameof<Diagnostic>(d => d.getLength), () => {
         it("should get the length", () => {
             expect(constError.getLength()).to.equal(1);