Simplify TypeNode parsing

ajafff · ajafff · commit dddbae5cbe9a · 2018-04-01T22:14:43.000+02:00
diff --git a/rules/noUnnecessaryTypeAnnotationRule.ts b/rules/noUnnecessaryTypeAnnotationRule.ts
@@ -302,10 +302,9 @@ function walk(ctx: Lint.WalkContext<IOptions>, checker: ts.TypeChecker) {
 }
 
 function removeSignatureReturn(str: string): string {
-    const sourceFile = ts.createSourceFile('tmp.ts', `var a:${str}`, ts.ScriptTarget.ESNext);
-    const signature = <ts.FunctionOrConstructorTypeNode>(<ts.VariableStatement>sourceFile.statements[0])
-        .declarationList.declarations[0].type!;
-    return sourceFile.text.substring(6, signature.parameters.end + 1);
+    const sourceFile = ts.createSourceFile('tmp.ts', `type T=${str}`, ts.ScriptTarget.ESNext);
+    const signature = <ts.FunctionOrConstructorTypeNode>(<ts.TypeAliasDeclaration>sourceFile.statements[0]).type;
+    return sourceFile.text.substring(7, signature.parameters.end + 1);
 }
 
 function getSignaturesOfType(type: ts.Type): ts.Signature[] {

Original file line number	Diff line number	Diff line change
`@@ -302,10 +302,9 @@ function walk(ctx: Lint.WalkContext<IOptions>, checker: ts.TypeChecker) {`
`302`	`302`	`}`
`303`	`303`
`304`	`304`	`function removeSignatureReturn(str: string): string {`
`305`		- const sourceFile = ts.createSourceFile('tmp.ts', `var a:${str}`, ts.ScriptTarget.ESNext);
`306`		`- const signature = <ts.FunctionOrConstructorTypeNode>(<ts.VariableStatement>sourceFile.statements[0])`
`307`		`- .declarationList.declarations[0].type!;`
`308`		`- return sourceFile.text.substring(6, signature.parameters.end + 1);`
	`305`	+ const sourceFile = ts.createSourceFile('tmp.ts', `type T=${str}`, ts.ScriptTarget.ESNext);
	`306`	`+ const signature = <ts.FunctionOrConstructorTypeNode>(<ts.TypeAliasDeclaration>sourceFile.statements[0]).type;`
	`307`	`+ return sourceFile.text.substring(7, signature.parameters.end + 1);`
`309`	`308`	`}`
`310`	`309`
`311`	`310`	`function getSignaturesOfType(type: ts.Type): ts.Signature[] {`