1. Add specific condition for one or no arg in PADDLE_ENFORCE

2. Add unit test for new enforce feature

test=develop

paddle/fluid/platform/enforce.h

@@ -258,7 +258,12 @@ inline void throw_on_error(T e) {
 #define PADDLE_THROW(...) \
   throw ::paddle::platform::EnforceNotMet(__FILE__, __LINE__, __VA_ARGS__)
 
-#define __PADDLE_THROW_ERROR(COND, ...)                                   \
+#define __PADDLE_THROW_ERROR_I(_, _9, _8, _7, _6, _5, _4, _3, _2, X_, ...) X_;
+
+#define __THROW_ON_ERROR_ONE_ARG(COND, ARG) \
+  ::paddle::platform::throw_on_error(COND, "%s", std::string(ARG));
+
+#define __PADDLE_THROW_ON_ERROR(COND, ...)                                \
   __PADDLE_THROW_ERROR_I(                                                 \
       __VA_ARGS__, ::paddle::platform::throw_on_error(COND, __VA_ARGS__), \
       ::paddle::platform::throw_on_error(COND, __VA_ARGS__),              \
@@ -268,15 +273,13 @@ inline void throw_on_error(T e) {
       ::paddle::platform::throw_on_error(COND, __VA_ARGS__),              \
       ::paddle::platform::throw_on_error(COND, __VA_ARGS__),              \
       ::paddle::platform::throw_on_error(COND, __VA_ARGS__),              \
-      ::paddle::platform::throw_on_error(COND))
-
-#define __PADDLE_THROW_ERROR_I(_, _9, _8, _7, _6, _5, _4, _3, _2, X_, ...) X_;
+      __THROW_ON_ERROR_ONE_ARG(COND, __VA_ARGS__))
 
 #define __PADDLE_UNARY_COMPARE(COND, ...)                 \
   do {                                                    \
     auto __cond = COND;                                   \
     if (UNLIKELY(::paddle::platform::is_error(__cond))) { \
-      __PADDLE_THROW_ERROR(__cond, __VA_ARGS__);          \
+      __PADDLE_THROW_ON_ERROR(__cond, __VA_ARGS__);       \
     }                                                     \
   } while (0)
 

paddle/fluid/platform/enforce_test.cc

@@ -37,6 +37,25 @@ TEST(ENFORCE, FAILED) {
         HasPrefix(StringPiece(error.what()), "Enforce is not ok 123 at all"));
   }
   EXPECT_TRUE(caught_exception);
+
+  caught_exception = false;
+  try {
+    PADDLE_ENFORCE(false, "Enforce is not ok at all");
+  } catch (paddle::platform::EnforceNotMet error) {
+    caught_exception = true;
+    EXPECT_TRUE(
+        HasPrefix(StringPiece(error.what()), "Enforce is not ok at all"));
+  }
+  EXPECT_TRUE(caught_exception);
+
+  caught_exception = false;
+  try {
+    PADDLE_ENFORCE(false);
+  } catch (paddle::platform::EnforceNotMet error) {
+    caught_exception = true;
+    EXPECT_NE(std::string(error.what()).find("  at "), 0);
+  }
+  EXPECT_TRUE(caught_exception);
 }
 
 TEST(ENFORCE, NO_ARG_OK) {