Add explanatory comments, consolidate main body

Author: uniqueiniquity

src/services/outliningElementsCollector.ts

@@ -3,11 +3,17 @@ namespace ts.OutliningElementsCollector {
     export function collectElements(sourceFile: SourceFile, cancellationToken: CancellationToken): OutliningSpan[] {
         const elements: OutliningSpan[] = [];
         const collapseText = "...";
+        let depth = 0;
+        const maxDepth = 20;
+
+        walk(sourceFile);
+        return elements;
 
-        function addOutliningSpan(hintSpanNode: Node, startElement: Node, endElement: Node, autoCollapse: boolean, fullStart: boolean) {
+        // If useFullStart is true, then the collapsing span includes leading whitespace, including linebreaks.
+        function addOutliningSpan(hintSpanNode: Node, startElement: Node, endElement: Node, autoCollapse: boolean, useFullStart: boolean) {
             if (hintSpanNode && startElement && endElement) {
                 const span: OutliningSpan = {
-                    textSpan: createTextSpanFromBounds(fullStart ? startElement.pos : startElement.getStart(), endElement.end),
+                    textSpan: createTextSpanFromBounds(useFullStart ? startElement.pos : startElement.getStart(), endElement.end),
                     hintSpan: createTextSpanFromBounds(startElement.getStart(), endElement.end),
                     bannerText: collapseText,
                     autoCollapse,
@@ -82,8 +88,6 @@ namespace ts.OutliningElementsCollector {
             return isFunctionBlock(node) && node.parent.kind !== SyntaxKind.ArrowFunction;
         }
 
-        let depth = 0;
-        const maxDepth = 20;
         function walk(n: Node): void {
             cancellationToken.throwIfCancellationRequested();
             if (depth > maxDepth) {
@@ -163,6 +167,9 @@ namespace ts.OutliningElementsCollector {
                     addOutliningSpan(n, openBrace, closeBrace, autoCollapse(n), /* fullStart */ true);
                     break;
                 }
+                // If the block has no leading keywords and is a member of an array literal,
+                // we again want to only collapse the span of the block.
+                // Otherwise, the collapsed section will include the end of the previous line.
                 case SyntaxKind.ObjectLiteralExpression:
                     const openBrace = findChildOfKind(n, SyntaxKind.OpenBraceToken, sourceFile);
                     const closeBrace = findChildOfKind(n, SyntaxKind.CloseBraceToken, sourceFile);
@@ -178,8 +185,5 @@ namespace ts.OutliningElementsCollector {
             forEachChild(n, walk);
             depth--;
         }
-
-        walk(sourceFile);
-        return elements;
     }
 }

tests/cases/fourslash/getOutliningForObjectsInArray.ts

@@ -1,13 +1,13 @@
 /// <reference path="fourslash.ts"/>
 
-////// objects in x should generate outlining spans that do not render in VS
+// objects in x should generate outlining spans that do not render in VS
 //// const x =[| [
 ////     [|{ a: 0 }|],
 ////     [|{ b: 1 }|],
 ////     [|{ c: 2 }|]
 //// ]|];
 ////
-////// objects in y should generate outlining spans that render as expected
+// objects in y should generate outlining spans that render as expected
 //// const y =[| [
 ////     [|{
 ////         a: 0
@@ -20,7 +20,7 @@
 ////     }|]
 //// ]|];
 ////
-////// same behavior for nested arrays
+// same behavior for nested arrays
 //// const w =[| [
 ////     [|[ 0 ]|],
 ////     [|[ 1 ]|],
@@ -39,7 +39,7 @@
 ////     ]|]
 //// ]|];
 ////
-////// multiple levels of nesting work as expected
+// multiple levels of nesting work as expected
 //// const z =[| [
 ////     [|[
 ////         [|{ hello: 0 }|]