Fixes PR17617: Crash on joining short if statements.

Now that we iterate on the formatting multiple times when we
have chains of preprocessor branches, we need to correctly reset
the token's previous and next pointer for the first / last token.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@193071 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Format/TokenAnnotator.h b/lib/Format/TokenAnnotator.h
index 91f1b4678a14ace3d323dc3337c77e2f944cf136..e51003bac822a71a3a84457f1ebfe1c88040d4b4 100644 (file)
--- a/lib/Format/TokenAnnotator.h
+++ b/lib/Format/TokenAnnotator.h
@@ -43,6 +43,11 @@ public:
         MustBeDeclaration(Line.MustBeDeclaration), MightBeFunctionDecl(false),
         StartsDefinition(false) {
     assert(!Line.Tokens.empty());
+
+    // Calculate Next and Previous for all tokens. Note that we must overwrite
+    // Next and Previous for every token, as previous formatting runs might have
+    // left them in a different state.
+    First->Previous = NULL;
     FormatToken *Current = First;
     for (std::list<UnwrappedLineNode>::const_iterator I = ++Line.Tokens.begin(),
                                                       E = Line.Tokens.end();
@@ -60,6 +65,7 @@ public:
       }
     }
     Last = Current;
+    Last->Next = NULL;
   }
 
   ~AnnotatedLine() {

diff --git a/unittests/Format/FormatTest.cpp b/unittests/Format/FormatTest.cpp
index 6a2d0d89b4cdd61e6a4ae5996c054e0ead12bdb7..a7de81b26782cd2ee278420846462966057eb056 100644 (file)
--- a/unittests/Format/FormatTest.cpp
+++ b/unittests/Format/FormatTest.cpp
@@ -2329,6 +2329,19 @@ TEST_F(FormatTest, LayoutStatementsAroundPreprocessorDirectives) {
                "int i;");
 }
 
+TEST_F(FormatTest, FormatsJoinedLinesOnSubsequentRuns) {
+  FormatStyle SingleLine = getLLVMStyle();
+  SingleLine.AllowShortIfStatementsOnASingleLine = true;
+  verifyFormat(
+      "#if 0\n"
+      "#elif 1\n"
+      "#endif\n"
+      "void foo() {\n"
+      "  if (test) foo2();\n"
+      "}",
+      SingleLine);
+}
+
 TEST_F(FormatTest, LayoutBlockInsideParens) {
   EXPECT_EQ("functionCall({ int i; });", format(" functionCall ( {int i;} );"));
   EXPECT_EQ("functionCall({\n"