clang-format: [JS] fix union type spacing in object & array types.

Summary:
Previously, clang-format would insert whitespace in union types nested in object
and array types, as it wouldn't recognize those as a type operator:

    const x: {foo: number | null};
    const x: [number | null];

While this is correct for actual binary operators, clang-format should not
insert whitespace into union and intersection types to mark those:

    const x: {foo: number|null};
    const x: [number|null];

This change propagates that the context is not an expression by inspecting
the preceding token and marking as non-expression if it was a type colon.

Reviewers: djasper

Subscribers: klimek

Differential Revision: https://reviews.llvm.org/D36136

llvm-svn: 310367

1 files changed, 9 insertions, 0 deletions

diff --git a/clang/lib/Format/TokenAnnotator.cpp b/clang/lib/Format/TokenAnnotator.cpp
index 7ea34d49be3..37583cdb8f4 100644
--- a/clang/lib/Format/TokenAnnotator.cpp
+++ b/clang/lib/Format/TokenAnnotator.cpp
@@ -372,6 +372,10 @@ private:
 
     ScopedContextCreator ContextCreator(*this, tok::l_square, BindingIncrease);
     Contexts.back().IsExpression = true;
+    if (Style.Language == FormatStyle::LK_JavaScript && Parent &&
+        Parent->is(TT_JsTypeColon))
+      Contexts.back().IsExpression = false;
+
     Contexts.back().ColonIsObjCMethodExpr = StartsObjCMethodExpr;
 
     while (CurrentToken) {
@@ -439,6 +443,9 @@ private:
       Contexts.back().ColonIsDictLiteral = true;
       if (Left->BlockKind == BK_BracedInit)
         Contexts.back().IsExpression = true;
+      if (Style.Language == FormatStyle::LK_JavaScript && Left->Previous &&
+          Left->Previous->is(TT_JsTypeColon))
+        Contexts.back().IsExpression = false;
 
       while (CurrentToken) {
         if (CurrentToken->is(tok::r_brace)) {
@@ -531,6 +538,8 @@ private:
              !Line.First->isOneOf(tok::kw_enum, tok::kw_case)) ||
             Contexts.back().ContextKind == tok::l_paren ||  // function params
             Contexts.back().ContextKind == tok::l_square || // array type
+            (!Contexts.back().IsExpression &&
+             Contexts.back().ContextKind == tok::l_brace) || // object type
             (Contexts.size() == 1 &&
              Line.MustBeDeclaration)) { // method/property declaration
           Contexts.back().IsExpression = false;