[clang-tidy] Enhance clang-tidy readability-simplify-boolean-expr check...

Enhance clang-tidy readability-simplify-boolean-expr check to handle chained
conditional assignment and chained conditional return.

Based on feedback from applying this tool to the clang/LLVM codebase, this
changeset improves the readability-simplify-boolean-expr check so that
conditional assignment or return statements at the end of a chain of if/else if
statements are left unchanged unless a configuration option is supplied.

http://reviews.llvm.org/D8996

Patch by Richard Thomson!

llvm-svn: 237541

1 files changed, 52 insertions, 0 deletions

diff --git a/clang-tools-extra/test/clang-tidy/readability-simplify-bool-expr.cpp b/clang-tools-extra/test/clang-tidy/readability-simplify-bool-expr.cpp
index 0658a17b278..708270fedf9 100644
--- a/clang-tools-extra/test/clang-tidy/readability-simplify-bool-expr.cpp
+++ b/clang-tools-extra/test/clang-tidy/readability-simplify-bool-expr.cpp
@@ -541,3 +541,55 @@ void complex_conditional_assignment_statements(int i) {
   } else
     f = false;
 }
+
+// unchanged: chained return statements, but ChainedConditionalReturn not set
+bool chained_conditional_compound_return(int i) {
+  if (i < 0) {
+    return true;
+  } else if (i < 10) {
+    return false;
+  } else if (i > 20) {
+    return true;
+  } else {
+    return false;
+  }
+}
+
+// unchanged: chained return statements, but ChainedConditionalReturn not set
+bool chained_conditional_return(int i) {
+  if (i < 0)
+    return true;
+  else if (i < 10)
+    return false;
+  else if (i > 20)
+    return true;
+  else
+    return false;
+}
+
+// unchanged: chained assignments, but ChainedConditionalAssignment not set
+void chained_conditional_compound_assignment(int i) {
+  bool b;
+  if (i < 0) {
+    b = true;
+  } else if (i < 10) {
+    b = false;
+  } else if (i > 20) {
+    b = true;
+  } else {
+    b = false;
+  }
+}
+
+// unchanged: chained return statements, but ChainedConditionalReturn not set
+void chained_conditional_assignment(int i) {
+  bool b;
+  if (i < 0)
+    b = true;
+  else if (i < 10)
+    b = false;
+  else if (i > 20)
+    b = true;
+  else
+    b = false;
+}