[PATCH] [clang-tidy] Add a checker for swapped literal arguments.

[Daniel Jasper]

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Comment at: clang-tidy/misc/CMakeLists.txt:6
@@ -5,2 +5,3 @@
   BoolPointerImplicitConversion.cpp
+  ImplicitArgumentConversion.cpp
   MiscTidyModule.cpp
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ImplicitArgumentConversion is not exactly what this does, I think. Maybe SwappedArgumentsCheck?

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Comment at: clang-tidy/misc/ImplicitArgumentConversion.cpp:33
@@ +32,3 @@
+  for (auto *Parm : Call->arguments()) {
+    // We only care about literals.
+    const Expr *PP = Parm->IgnoreImpCasts();
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Why do we only care about literals?

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Comment at: clang-tidy/misc/ImplicitArgumentConversion.cpp:34
@@ +33,3 @@
+    // We only care about literals.
+    const Expr *PP = Parm->IgnoreImpCasts();
+    if (!isa<CharacterLiteral>(PP) && !isa<CXXBoolLiteralExpr>(PP) &&
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Maybe IgnoreParenImpCasts()?

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Comment at: clang-tidy/misc/ImplicitArgumentConversion.cpp:52
@@ +51,3 @@
+  // most likely a swap.
+  if (NumConversions >= 2 && DeclTypes == CallTypes) {
+    diag(Call->getLocStart(),
----------------
Mhmm. This seems like a very crude way of doing this. Might be ok for a first iteration, but it seems like we could actually be much smarter and check if there is a re-ordering that would fit better (and even extend the analysis to more than two parameters, no)?

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Comment at: clang-tidy/misc/ImplicitArgumentConversion.h:18
@@ +17,3 @@
+
+/// \brief 
+class ImplicitArgumentConversion : public ClangTidyCheck {
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This is VERY brief ;-)

http://reviews.llvm.org/D4457