Add simple support for tags in YAML I/O

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194644 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 85 insertions, 0 deletions

diff --git a/unittests/Support/YAMLIOTest.cpp b/unittests/Support/YAMLIOTest.cpp
index 8ae05f4..db70b91 100644
--- a/unittests/Support/YAMLIOTest.cpp
+++ b/unittests/Support/YAMLIOTest.cpp
@@ -989,6 +989,91 @@ TEST(YAMLIO, TestSequenceDocListWriteAndRead) {
   }
 }
 
+//===----------------------------------------------------------------------===//
+//  Test document tags
+//===----------------------------------------------------------------------===//
+
+struct MyDouble {
+  MyDouble() : value(0.0) { }
+  MyDouble(double x) : value(x) { }
+  double value;
+};
+
+LLVM_YAML_IS_DOCUMENT_LIST_VECTOR(MyDouble);
+
+
+namespace llvm {
+namespace yaml {
+  template <>
+  struct MappingTraits<MyDouble> {
+    static void mapping(IO &io, MyDouble &d) {
+      if (io.mapTag("!decimal", true)) {
+        mappingDecimal(io, d);
+      } else if (io.mapTag("!fraction")) {
+        mappingFraction(io, d);
+      }
+    }
+    static void mappingDecimal(IO &io, MyDouble &d) {
+      io.mapRequired("value", d.value);
+    }
+    static void mappingFraction(IO &io, MyDouble &d) {
+        double num, denom;
+        io.mapRequired("numerator",      num);
+        io.mapRequired("denominator",    denom);
+        // convert fraction to double
+        d.value = num/denom;
+    }
+  };
+ }
+}
+
+
+//
+// Test the reading of two different tagged yaml documents.
+//
+TEST(YAMLIO, TestTaggedDocuments) {
+  std::vector<MyDouble> docList;
+  Input yin("--- !decimal\nvalue:  3.0\n"
+            "--- !fraction\nnumerator:  9.0\ndenominator:  2\n...\n");
+  yin >> docList;
+  EXPECT_FALSE(yin.error());
+  EXPECT_EQ(docList.size(), 2UL);
+  EXPECT_EQ(docList[0].value, 3.0);
+  EXPECT_EQ(docList[1].value, 4.5);
+}
+
+
+
+//
+// Test writing then reading back tagged documents
+//
+TEST(YAMLIO, TestTaggedDocumentsWriteAndRead) {
+  std::string intermediate;
+  {
+    MyDouble a(10.25);
+    MyDouble b(-3.75);
+    std::vector<MyDouble> docList;
+    docList.push_back(a);
+    docList.push_back(b);
+
+    llvm::raw_string_ostream ostr(intermediate);
+    Output yout(ostr);
+    yout << docList;
+  }
+
+  {
+    Input yin(intermediate);
+    std::vector<MyDouble> docList2;
+    yin >> docList2;
+
+    EXPECT_FALSE(yin.error());
+    EXPECT_EQ(docList2.size(), 2UL);
+    EXPECT_EQ(docList2[0].value, 10.25);
+    EXPECT_EQ(docList2[1].value, -3.75);
+  }
+}
+
+
 
 //===----------------------------------------------------------------------===//
 //  Test error handling