Pvb/discover code actions

src/harness/fourslash.ts

@@ -2958,7 +2958,7 @@ namespace FourSlashInterface {
         }
 
         public isValidBraceCompletionAtPosition(openingBrace: string) {
-            this.state.verifyBraceCompletionAtPostion(this.negative, openingBrace);
+            this.state.verifyBraceCompletionAtPosition(this.negative, openingBrace);
         }
     }
 

src/services/codefixes/codeFixProvider.ts

@@ -3,14 +3,19 @@ namespace ts {
     export interface CodeAction {
         name: string;
         errorCodes: string[];
-        getTextChanges(sourceFile: SourceFile, start: number, end: number): FileTextChanges[];
+        getTextChanges(context: CodeActionContext): FileTextChanges[];
+    }
+
+    export class CodeActionContext {
+        constructor(public errorCode: string, public sourceFile: SourceFile, public span: TextSpan, public checker: TypeChecker) {
+        }
     }
 
     export namespace codeFix {
         var codeActions: Map<CodeAction[]> = {};
 
         export function registerCodeFix(fix: CodeAction) {
-            forEach( fix.errorCodes, error => {
+            forEach(fix.errorCodes, error => {
                 let fixes = codeActions[error];
                 if (!fixes) {
                     fixes = [];
@@ -26,14 +31,14 @@ namespace ts {
                 return getKeys(codeActions);
             }
 
-            public getFixes(errorCode: string, sourceFile: SourceFile, start: number, end: number): CodeFix[] {
-                const actions = codeActions[errorCode];
+            public getFixes(context: CodeActionContext): CodeFix[] {
+                const actions = codeActions[context.errorCode];
                 const fixes: CodeFix[] = [];
 
                 Debug.assert(actions && actions.length > 0, "No fixes found for error: '${errorCode}'.");
 
                 forEach(actions, a => {
-                    const textChanges = a.getTextChanges(sourceFile, start, end);
+                    const textChanges = a.getTextChanges(context);
                     if (textChanges && textChanges.length > 0) {
                         fixes.push({ description: a.name, changes: textChanges });
                     }

src/services/codefixes/superFixes.ts

@@ -8,8 +8,9 @@ namespace ts.codeFix {
     registerCodeFix({
         name: getLocaleSpecificMessage(Diagnostics.Add_missing_super_call),
         errorCodes: ["TS2377"],
-        getTextChanges: (sourceFile: SourceFile, start: number, end: number) => {
-            const token = getTokenAtPosition(sourceFile, start);
+        getTextChanges: (context: CodeActionContext) => {
+            const sourceFile = context.sourceFile;
+            const token = getTokenAtPosition(sourceFile, context.span.start);
             Debug.assert(token.kind === SyntaxKind.ConstructorKeyword, "Failed to find the constructor.");
 
             const newPosition = getOpenBraceEnd(<ConstructorDeclaration>token.parent, sourceFile);
@@ -21,8 +22,10 @@ namespace ts.codeFix {
     registerCodeFix({
         name: getLocaleSpecificMessage(Diagnostics.Make_super_call_the_first_statement_in_the_constructor),
         errorCodes: ["TS17009"],
-        getTextChanges: (sourceFile: SourceFile, start: number, end: number) => {
-            const token = getTokenAtPosition(sourceFile, start);
+        getTextChanges: (context: CodeActionContext) => {
+            const sourceFile = context.sourceFile;
+
+            const token = getTokenAtPosition(sourceFile, context.span.start);
             const constructor = getContainingFunction(token);
             Debug.assert(constructor.kind === SyntaxKind.Constructor, "Failed to find the constructor.");
 

src/services/services.ts

@@ -7708,11 +7708,13 @@ namespace ts {
         function getCodeFixesAtPosition(fileName: string, start: number, end: number, errorCodes: string[]): CodeFix[] {
             synchronizeHostData();
             const sourceFile = getValidSourceFile(fileName);
-
+            const checker = program.getTypeChecker();
             let allFixes: CodeFix[] = [];
 
             forEach(errorCodes, error => {
-                const fixes = codeFixProvider.getFixes(error, sourceFile, start, end);
+                const context = new CodeActionContext(error, sourceFile, { start, length: end - start }, checker);
+
+                const fixes = codeFixProvider.getFixes(context);
                 if (fixes) {
                     allFixes = allFixes.concat(fixes);
                 }