YAML: Add an optional 'flow' field to the mapping trait to allow flow mapping output.

This patch adds an optional 'flow' field to the MappingTrait
class so that yaml IO will be able to output flow mappings.

Reviewers: Justin Bogner

Differential Revision: http://reviews.llvm.org/D9450

llvm-svn: 236456

1 files changed, 46 insertions, 4 deletions

diff --git a/llvm/lib/Support/YAMLTraits.cpp b/llvm/lib/Support/YAMLTraits.cpp
index 16821738190..8ef36a33280 100644
--- a/llvm/lib/Support/YAMLTraits.cpp
+++ b/llvm/lib/Support/YAMLTraits.cpp
@@ -168,6 +168,10 @@ void Input::endMapping() {
   }
 }
 
+void Input::beginFlowMapping() { beginMapping(); }
+
+void Input::endFlowMapping() { endMapping(); }
+
 unsigned Input::beginSequence() {
   if (SequenceHNode *SQ = dyn_cast<SequenceHNode>(CurrentNode))
     return SQ->Entries.size();
@@ -393,6 +397,7 @@ Output::Output(raw_ostream &yout, void *context)
       Out(yout),
       Column(0),
       ColumnAtFlowStart(0),
+      ColumnAtMapFlowStart(0),
       NeedBitValueComma(false),
       NeedFlowSequenceComma(false),
       EnumerationMatchFound(false),
@@ -427,8 +432,13 @@ bool Output::preflightKey(const char *Key, bool Required, bool SameAsDefault,
                           bool &UseDefault, void *&) {
   UseDefault = false;
   if (Required || !SameAsDefault) {
-    this->newLineCheck();
-    this->paddedKey(Key);
+    auto State = StateStack.back();
+    if (State == inFlowMapFirstKey || State == inFlowMapOtherKey) {
+      flowKey(Key);
+    } else {
+      this->newLineCheck();
+      this->paddedKey(Key);
+    }
     return true;
   }
   return false;
@@ -438,9 +448,24 @@ void Output::postflightKey(void *) {
   if (StateStack.back() == inMapFirstKey) {
     StateStack.pop_back();
     StateStack.push_back(inMapOtherKey);
+  } else if (StateStack.back() == inFlowMapFirstKey) {
+    StateStack.pop_back();
+    StateStack.push_back(inFlowMapOtherKey);
   }
 }
 
+void Output::beginFlowMapping() {
+  StateStack.push_back(inFlowMapFirstKey);
+  this->newLineCheck();
+  ColumnAtMapFlowStart = Column;
+  output("{ ");
+}
+
+void Output::endFlowMapping() {
+  StateStack.pop_back();
+  this->outputUpToEndOfLine(" }");
+}
+
 void Output::beginDocuments() {
   this->outputUpToEndOfLine("---");
 }
@@ -607,7 +632,9 @@ void Output::output(StringRef s) {
 
 void Output::outputUpToEndOfLine(StringRef s) {
   this->output(s);
-  if (StateStack.empty() || StateStack.back() != inFlowSeq)
+  if (StateStack.empty() || (StateStack.back() != inFlowSeq &&
+                             StateStack.back() != inFlowMapFirstKey &&
+                             StateStack.back() != inFlowMapOtherKey))
     NeedsNewLine = true;
 }
 
@@ -634,7 +661,8 @@ void Output::newLineCheck() {
   if (StateStack.back() == inSeq) {
     OutputDash = true;
   } else if ((StateStack.size() > 1) && ((StateStack.back() == inMapFirstKey) ||
-             (StateStack.back() == inFlowSeq)) &&
+             (StateStack.back() == inFlowSeq) ||
+             (StateStack.back() == inFlowMapFirstKey)) &&
              (StateStack[StateStack.size() - 2] == inSeq)) {
     --Indent;
     OutputDash = true;
@@ -659,6 +687,20 @@ void Output::paddedKey(StringRef key) {
     output(" ");
 }
 
+void Output::flowKey(StringRef Key) {
+  if (StateStack.back() == inFlowMapOtherKey)
+    output(", ");
+  if (Column > 70) {
+    output("\n");
+    for (int I = 0; I < ColumnAtMapFlowStart; ++I)
+      output(" ");
+    Column = ColumnAtMapFlowStart;
+    output("  ");
+  }
+  output(Key);
+  output(": ");
+}
+
 //===----------------------------------------------------------------------===//
 //  traits for built-in types
 //===----------------------------------------------------------------------===//