From 2efc92d1dc35c5683cb7bcf438f5f72351a19220 Mon Sep 17 00:00:00 2001
From: Andy <anhans@microsoft.com>
Date: Mon, 18 Dec 2017 10:54:54 -0800
Subject: [PATCH] Adjust formatting rule priority: Never delete space after
 `case` (#20615)

---
 src/services/formatting/rules.ts                      | 11 ++++++-----
 .../fourslash/server/formatBracketInSwitchCase.ts     | 11 +++++++++++
 2 files changed, 17 insertions(+), 5 deletions(-)
 create mode 100644 tests/cases/fourslash/server/formatBracketInSwitchCase.ts

diff --git a/src/services/formatting/rules.ts b/src/services/formatting/rules.ts
index 8214ffd6f2d..91c133ca352 100644
--- a/src/services/formatting/rules.ts
+++ b/src/services/formatting/rules.ts
@@ -302,7 +302,7 @@ namespace ts.formatting {
             rule("NoSpaceAfterTypeAssertion", SyntaxKind.GreaterThanToken, anyToken, [isOptionDisabledOrUndefined("insertSpaceAfterTypeAssertion"), isNonJsxSameLineTokenContext, isTypeAssertionContext], RuleAction.Delete),
         ];
 
-        // These rules are lower in priority than user-configurable
+        // These rules are lower in priority than user-configurable. Rules earlier in this list have priority over rules later in the list.
         const lowPriorityCommonRules = [
             // Space after keyword but not before ; or : or ?
             rule("NoSpaceBeforeSemicolon", anyToken, SyntaxKind.SemicolonToken, [isNonJsxSameLineTokenContext], RuleAction.Delete),
@@ -312,10 +312,6 @@ namespace ts.formatting {
             rule("SpaceBeforeOpenBraceInTypeScriptDeclWithBlock", typeScriptOpenBraceLeftTokenRange, SyntaxKind.OpenBraceToken, [isOptionDisabledOrUndefinedOrTokensOnSameLine("placeOpenBraceOnNewLineForFunctions"), isTypeScriptDeclWithBlockContext, isNotFormatOnEnter, isSameLineTokenOrBeforeBlockContext], RuleAction.Space, RuleFlags.CanDeleteNewLines),
 
             rule("NoSpaceBeforeComma", anyToken, SyntaxKind.CommaToken, [isNonJsxSameLineTokenContext], RuleAction.Delete),
-            // No space before and after indexer
-            rule("NoSpaceBeforeOpenBracket", anyTokenExcept(SyntaxKind.AsyncKeyword), SyntaxKind.OpenBracketToken, [isNonJsxSameLineTokenContext], RuleAction.Delete),
-            rule("NoSpaceAfterCloseBracket", SyntaxKind.CloseBracketToken, anyToken, [isNonJsxSameLineTokenContext, isNotBeforeBlockInFunctionDeclarationContext], RuleAction.Delete),
-            rule("SpaceAfterSemicolon", SyntaxKind.SemicolonToken, anyToken, [isNonJsxSameLineTokenContext], RuleAction.Space),
 
             // Add a space between statements. All keywords except (do,else,case) has open/close parens after them.
             // So, we have a rule to add a space for [),Any], [do,Any], [else,Any], and [case,Any]
@@ -327,6 +323,11 @@ namespace ts.formatting {
                 RuleAction.Space),
             // This low-pri rule takes care of "try {" and "finally {" in case the rule SpaceBeforeOpenBraceInControl didn't execute on FormatOnEnter.
             rule("SpaceAfterTryFinally", [SyntaxKind.TryKeyword, SyntaxKind.FinallyKeyword], SyntaxKind.OpenBraceToken, [isNonJsxSameLineTokenContext], RuleAction.Space),
+
+            // No space before and after indexer `x[]`
+            rule("NoSpaceBeforeOpenBracket", anyTokenExcept(SyntaxKind.AsyncKeyword), SyntaxKind.OpenBracketToken, [isNonJsxSameLineTokenContext], RuleAction.Delete),
+            rule("NoSpaceAfterCloseBracket", SyntaxKind.CloseBracketToken, anyToken, [isNonJsxSameLineTokenContext, isNotBeforeBlockInFunctionDeclarationContext], RuleAction.Delete),
+            rule("SpaceAfterSemicolon", SyntaxKind.SemicolonToken, anyToken, [isNonJsxSameLineTokenContext], RuleAction.Space),
         ];
 
         return [
diff --git a/tests/cases/fourslash/server/formatBracketInSwitchCase.ts b/tests/cases/fourslash/server/formatBracketInSwitchCase.ts
new file mode 100644
index 00000000000..116138f9743
--- /dev/null
+++ b/tests/cases/fourslash/server/formatBracketInSwitchCase.ts
@@ -0,0 +1,11 @@
+/// <reference path="../fourslash.ts"/>
+
+////switch (x) {
+////    case[]:
+////}
+
+format.document();
+verify.currentFileContentIs(
+`switch (x) {
+    case []:
+}`);