Review comments

src/compiler/utilities.ts

@@ -179,6 +179,32 @@ namespace ts {
         return node.pos;
     }
 
+    export function getEndLinePosition(line: number, sourceFile: SourceFile): number {
+        Debug.assert(line >= 0);
+        let lineStarts = getLineStarts(sourceFile);
+
+        let lineIndex = line;
+        if (lineIndex + 1 === lineStarts.length) {
+            // last line - return EOF
+            return sourceFile.text.length - 1;
+        }
+        else {
+            // current line start
+            let start = lineStarts[lineIndex];
+            // take the start position of the next line -1 = it should be some line break
+            let pos = lineStarts[lineIndex + 1] - 1;
+            Debug.assert(isLineBreak(sourceFile.text.charCodeAt(pos)));
+            // walk backwards skipping line breaks, stop the the beginning of current line.
+            // i.e:
+            // <some text>
+            // $ <- end of line for this position should match the start position
+            while (start <= pos && isLineBreak(sourceFile.text.charCodeAt(pos))) {
+                pos--;
+            }
+            return pos;
+        }
+    }
+
     // Returns true if this node is missing from the actual source code. A 'missing' node is different
     // from 'undefined/defined'. When a node is undefined (which can happen for optional nodes
     // in the tree), it is definitely missing. However, a node may be defined, but still be
@@ -366,18 +392,15 @@ namespace ts {
 
     function getErrorSpanForArrowFunction(sourceFile: SourceFile, node: ArrowFunction): TextSpan {
         const pos = skipTrivia(sourceFile.text, node.pos);
-
         if (node.body && node.body.kind === SyntaxKind.Block) {
-            const {line: startLine } = getLineAndCharacterOfPosition(sourceFile, node.body.pos);
-            const {line: endLine } = getLineAndCharacterOfPosition(sourceFile, node.body.end);
+            const { line: startLine } = getLineAndCharacterOfPosition(sourceFile, node.body.pos);
+            const { line: endLine } = getLineAndCharacterOfPosition(sourceFile, node.body.end);
             if (startLine < endLine) {
-                // The arrow function body spans multiple lines, 
-                // make the error span be the first line.
-                const endOfFirstLine = getLineStarts(sourceFile)[startLine + 1] - 1;
-                return createTextSpan(pos, endOfFirstLine - pos);
+                // The arrow function spans multiple lines, 
+                // make the error span be the first line, inclusive.
+                return createTextSpan(pos, getEndLinePosition(startLine, sourceFile) - pos + 1);
             }
         }
-
         return createTextSpanFromBounds(pos, node.end);
     }
 

src/services/utilities.ts

@@ -6,32 +6,6 @@ namespace ts {
         list: Node;
     }
 
-    export function getEndLinePosition(line: number, sourceFile: SourceFile): number {
-        Debug.assert(line >= 0);
-        let lineStarts = sourceFile.getLineStarts();
-
-        let lineIndex = line;
-        if (lineIndex + 1 === lineStarts.length) {
-            // last line - return EOF
-            return sourceFile.text.length - 1;
-        }
-        else {
-            // current line start
-            let start = lineStarts[lineIndex];
-            // take the start position of the next line -1 = it should be some line break
-            let pos = lineStarts[lineIndex + 1] - 1;
-            Debug.assert(isLineBreak(sourceFile.text.charCodeAt(pos)));
-            // walk backwards skipping line breaks, stop the the beginning of current line.
-            // i.e:
-            // <some text>
-            // $ <- end of line for this position should match the start position
-            while (start <= pos && isLineBreak(sourceFile.text.charCodeAt(pos))) {
-                pos--;
-            }
-            return pos;
-        }
-    }
-
     export function getLineStartPositionForPosition(position: number, sourceFile: SourceFile): number {
         let lineStarts = sourceFile.getLineStarts();
         let line = sourceFile.getLineAndCharacterOfPosition(position).line;

tests/baselines/reference/arrowFunctionErrorSpan.errors.txt

@@ -0,0 +1,111 @@
+tests/cases/compiler/arrowFunctionErrorSpan.ts(4,3): error TS2345: Argument of type '() => void' is not assignable to parameter of type '() => number'.
+  Type 'void' is not assignable to type 'number'.
+tests/cases/compiler/arrowFunctionErrorSpan.ts(7,3): error TS2345: Argument of type '() => void' is not assignable to parameter of type '() => number'.
+  Type 'void' is not assignable to type 'number'.
+tests/cases/compiler/arrowFunctionErrorSpan.ts(12,3): error TS2345: Argument of type '() => void' is not assignable to parameter of type '() => number'.
+  Type 'void' is not assignable to type 'number'.
+tests/cases/compiler/arrowFunctionErrorSpan.ts(17,3): error TS2345: Argument of type '() => void' is not assignable to parameter of type '() => number'.
+  Type 'void' is not assignable to type 'number'.
+tests/cases/compiler/arrowFunctionErrorSpan.ts(18,5): error TS1200: Line terminator not permitted before arrow.
+tests/cases/compiler/arrowFunctionErrorSpan.ts(21,3): error TS2345: Argument of type '(a: any, b: any, c: any, d: any) => void' is not assignable to parameter of type '() => number'.
+tests/cases/compiler/arrowFunctionErrorSpan.ts(28,7): error TS2345: Argument of type '() => void' is not assignable to parameter of type '() => number'.
+  Type 'void' is not assignable to type 'number'.
+tests/cases/compiler/arrowFunctionErrorSpan.ts(32,7): error TS2345: Argument of type '() => void' is not assignable to parameter of type '() => number'.
+  Type 'void' is not assignable to type 'number'.
+tests/cases/compiler/arrowFunctionErrorSpan.ts(36,7): error TS2345: Argument of type '() => void' is not assignable to parameter of type '() => number'.
+  Type 'void' is not assignable to type 'number'.
+tests/cases/compiler/arrowFunctionErrorSpan.ts(43,5): error TS2345: Argument of type '() => void' is not assignable to parameter of type '() => number'.
+  Type 'void' is not assignable to type 'number'.
+tests/cases/compiler/arrowFunctionErrorSpan.ts(52,3): error TS2345: Argument of type '(_: any) => number' is not assignable to parameter of type '() => number'.
+
+
+==== tests/cases/compiler/arrowFunctionErrorSpan.ts (11 errors) ====
+    function f(a: () => number) { }
+    
+    // oneliner
+    f(() => { });
+      ~~~~~~~~~
+!!! error TS2345: Argument of type '() => void' is not assignable to parameter of type '() => number'.
+!!! error TS2345:   Type 'void' is not assignable to type 'number'.
+    
+    // multiline, body
+    f(() => {
+      ~~~~~~~
+!!! error TS2345: Argument of type '() => void' is not assignable to parameter of type '() => number'.
+!!! error TS2345:   Type 'void' is not assignable to type 'number'.
+    
+    });
+    
+    // multiline 2, body
+    f(() => {
+      ~~~~~~~
+!!! error TS2345: Argument of type '() => void' is not assignable to parameter of type '() => number'.
+!!! error TS2345:   Type 'void' is not assignable to type 'number'.
+    
+    });
+    
+    // multiline 3, arrow on a new line
+    f(()
+      ~~
+        => { });
+    ~~~~~~~~~~
+!!! error TS2345: Argument of type '() => void' is not assignable to parameter of type '() => number'.
+!!! error TS2345:   Type 'void' is not assignable to type 'number'.
+        ~~
+!!! error TS1200: Line terminator not permitted before arrow.
+    
+    // multiline 4, arguments
+    f((a,
+      ~~~
+        b,
+    ~~~~~~
+        c,
+    ~~~~~~
+        d) => { });
+    ~~~~~~~~~~~~~
+!!! error TS2345: Argument of type '(a: any, b: any, c: any, d: any) => void' is not assignable to parameter of type '() => number'.
+    
+    // single line with a comment
+    f(/*
+        */() => { });
+          ~~~~~~~~~
+!!! error TS2345: Argument of type '() => void' is not assignable to parameter of type '() => number'.
+!!! error TS2345:   Type 'void' is not assignable to type 'number'.
+    
+    // multi line with a comment
+    f(/*
+        */() => { });
+          ~~~~~~~~~
+!!! error TS2345: Argument of type '() => void' is not assignable to parameter of type '() => number'.
+!!! error TS2345:   Type 'void' is not assignable to type 'number'.
+    
+    // multi line with a comment 2
+    f(/*
+        */() => { 
+          ~~~~~~~~
+!!! error TS2345: Argument of type '() => void' is not assignable to parameter of type '() => number'.
+!!! error TS2345:   Type 'void' is not assignable to type 'number'.
+    
+        });
+    
+    // multi line with a comment 3
+    f(  // comment 1
+        // comment 2
+        () =>
+        ~~~~~
+!!! error TS2345: Argument of type '() => void' is not assignable to parameter of type '() => number'.
+!!! error TS2345:   Type 'void' is not assignable to type 'number'.
+        // comment 3
+        {
+            // comment 4
+        }
+        // comment 5
+    ); 
+    
+    // body is not a block
+    f(_ => 1 +
+      ~~~~~~~~
+        2);
+    ~~~~~
+!!! error TS2345: Argument of type '(_: any) => number' is not assignable to parameter of type '() => number'.
+    

tests/baselines/reference/arrowFunctionErrorSpan.js

@@ -0,0 +1,89 @@
+//// [arrowFunctionErrorSpan.ts]
+function f(a: () => number) { }
+
+// oneliner
+f(() => { });
+
+// multiline, body
+f(() => {
+
+});
+
+// multiline 2, body
+f(() => {
+
+});
+
+// multiline 3, arrow on a new line
+f(()
+    => { });
+
+// multiline 4, arguments
+f((a,
+    b,
+    c,
+    d) => { });
+
+// single line with a comment
+f(/*
+    */() => { });
+
+// multi line with a comment
+f(/*
+    */() => { });
+
+// multi line with a comment 2
+f(/*
+    */() => { 
+
+    });
+
+// multi line with a comment 3
+f(  // comment 1
+    // comment 2
+    () =>
+    // comment 3
+    {
+        // comment 4
+    }
+    // comment 5
+); 
+
+// body is not a block
+f(_ => 1 +
+    2);
+
+
+//// [arrowFunctionErrorSpan.js]
+function f(a) { }
+// oneliner
+f(function () { });
+// multiline, body
+f(function () {
+});
+// multiline 2, body
+f(function () {
+});
+// multiline 3, arrow on a new line
+f(function () { });
+// multiline 4, arguments
+f(function (a, b, c, d) { });
+// single line with a comment
+f(/*
+    */ function () { });
+// multi line with a comment
+f(/*
+    */ function () { });
+// multi line with a comment 2
+f(/*
+    */ function () {
+});
+// multi line with a comment 3
+f(// comment 1
+// comment 2
+function () {
+    // comment 4
+});
+// body is not a block
+f(function (_) { return 1 +
+    2; });

tests/cases/compiler/arrowFunctionErrorSpan.ts

@@ -0,0 +1,53 @@
+function f(a: () => number) { }
+
+// oneliner
+f(() => { });
+
+// multiline, body
+f(() => {
+
+});
+
+// multiline 2, body
+f(() => {
+
+});
+
+// multiline 3, arrow on a new line
+f(()
+    => { });
+
+// multiline 4, arguments
+f((a,
+    b,
+    c,
+    d) => { });
+
+// single line with a comment
+f(/*
+    */() => { });
+
+// multi line with a comment
+f(/*
+    */() => { });
+
+// multi line with a comment 2
+f(/*
+    */() => { 
+
+    });
+
+// multi line with a comment 3
+f(  // comment 1
+    // comment 2
+    () =>
+    // comment 3
+    {
+        // comment 4
+    }
+    // comment 5
+); 
+
+// body is not a block
+f(_ => 1 +
+    2);