Use getTextOfNode over getTextOfNodeFromSourceText(getSourceFileOfNode(node))

src/compiler/binder.ts

@@ -1996,7 +1996,7 @@ namespace ts {
 
         /// Should be called only on prologue directives (isPrologueDirective(node) should be true)
         function isUseStrictPrologueDirective(node: ExpressionStatement): boolean {
-            const nodeText = getTextOfNodeFromSourceText(file.text, node.expression);
+            const nodeText = getSourceTextOfNodeFromSourceFile(file, node.expression);
 
             // Note: the node text must be exactly "use strict" or 'use strict'.  It is not ok for the
             // string to contain unicode escapes (as per ES5).

src/compiler/checker.ts

@@ -22811,8 +22811,7 @@ namespace ts {
                                      return "quit";
                                  }
                                  if (current.kind === SyntaxKind.LabeledStatement && (<LabeledStatement>current).label.escapedText === node.label.escapedText) {
-                                     const sourceFile = getSourceFileOfNode(node);
-                                     grammarErrorOnNode(node.label, Diagnostics.Duplicate_label_0, getTextOfNodeFromSourceText(sourceFile.text, node.label));
+                                     grammarErrorOnNode(node.label, Diagnostics.Duplicate_label_0, getTextOfNode(node.label));
                                      return true;
                                  }
                              });

src/compiler/utilities.ts

@@ -314,20 +314,15 @@ namespace ts {
     }
 
     export function getSourceTextOfNodeFromSourceFile(sourceFile: SourceFile, node: Node, includeTrivia = false): string {
-        if (nodeIsMissing(node)) {
-            return "";
-        }
-
-        const text = sourceFile.text;
-        return text.substring(includeTrivia ? node.pos : skipTrivia(text, node.pos), node.end);
+        return getTextOfNodeFromSourceText(sourceFile.text, node, includeTrivia);
     }
 
-    export function getTextOfNodeFromSourceText(sourceText: string, node: Node): string {
+    export function getTextOfNodeFromSourceText(sourceText: string, node: Node, includeTrivia = false): string {
         if (nodeIsMissing(node)) {
             return "";
         }
 
-        return sourceText.substring(skipTrivia(sourceText, node.pos), node.end);
+        return sourceText.substring(includeTrivia ? node.pos : skipTrivia(sourceText, node.pos), node.end);
     }
 
     export function getTextOfNode(node: Node, includeTrivia = false): string {

src/harness/typeWriter.ts

@@ -72,8 +72,7 @@ class TypeWriterWalker {
     private writeTypeOrSymbol(node: ts.Node, isSymbolWalk: boolean): TypeWriterResult {
         const actualPos = ts.skipTrivia(this.currentSourceFile.text, node.pos);
         const lineAndCharacter = this.currentSourceFile.getLineAndCharacterOfPosition(actualPos);
-        const sourceText = ts.getTextOfNodeFromSourceText(this.currentSourceFile.text, node);
-
+        const sourceText = ts.getSourceTextOfNodeFromSourceFile(this.currentSourceFile, node);
 
         if (!isSymbolWalk) {
             // Workaround to ensure we output 'C' instead of 'typeof C' for base class expressions