Fix #484, support multiple message parts in assert

Also modified the AST for regular asserts, for future proofing and
easier implementation.

Author: WebFreak001

src/dparse/ast.d

@@ -874,11 +874,21 @@ final class AssertArguments : BaseNode
 {
     override void accept(ASTVisitor visitor) const
     {
-        mixin (visitIfNotNull!(assertion, message));
+        mixin (visitIfNotNull!(assertion, messageParts));
     }
+
     /** */ ExpressionNode assertion;
-    /** */ ExpressionNode message;
+    /** */ ExpressionNode[] messageParts;
     mixin OpEquals;
+
+    deprecated("use firstMessage or process all messageParts instead")
+    alias message = firstMessage;
+
+    /// Returns `messageParts[0]` or `null` if no messageParts.
+    inout(ExpressionNode) firstMessage() inout nothrow pure @nogc @safe
+    {
+        return messageParts.length ? messageParts[0] : null;
+    }
 }
 
 ///

src/dparse/formatter.d

@@ -406,18 +406,13 @@ class Formatter(Sink)
     {
         debug(verbose) writeln("AssertExpression");
 
-        /**
-        AssignExpression assertion;
-        AssignExpression message;
-        **/
-
         with(assertArguments)
         {
             format(assertion);
-            if (message)
+            foreach (part; messageParts)
             {
                 put(", ");
-                format(message);
+                format(part);
             }
         }
     }

src/dparse/parser.d

@@ -350,7 +350,7 @@ class Parser
      * Parses an ArgumentList.
      *
      * $(GRAMMAR $(RULEDEF argumentList):
-     *     $(RULE assignExpression) ($(LITERAL ',') $(RULE assignExpression)?)*
+     *     $(RULE assignExpression) ($(LITERAL ',') $(RULE assignExpression)?)* $(LITERAL ',')?
      *     ;)
      */
     ArgumentList parseArgumentList()
@@ -1037,24 +1037,25 @@ class Parser
      * Parses an AssertArguments
      *
      * $(GRAMMAR $(RULEDEF assertArguments):
-     *     $(RULE assignExpression) ($(LITERAL ',') $(RULE assignExpression))? $(LITERAL ',')?
+     *     $(RULE assignExpression) ($(LITERAL ',') $(RULE assignExpression))* $(LITERAL ',')?
      *     ;)
      */
     AssertArguments parseAssertArguments()
     {
         auto startIndex = index;
         auto node = allocator.make!AssertArguments;
         mixin(parseNodeQ!(`node.assertion`, `AssignExpression`));
-        if (currentIs(tok!","))
-            advance();
-        if (currentIs(tok!")"))
+
+        StackBuffer items;
+        while (currentIs(tok!","))
         {
-            node.tokens = tokens[startIndex .. index];
-            return node;
-        }
-        mixin(parseNodeQ!(`node.message`, `AssignExpression`));
-        if (currentIs(tok!","))
             advance();
+            if (currentIs(tok!")"))
+                break;
+            if (!items.put(parseAssignExpression()))
+                return null;
+        }
+        ownArray(node.messageParts, items);
         node.tokens = tokens[startIndex .. index];
         return node;
     }

test/ast_checks/assert_args.d

@@ -0,0 +1 @@
+static assert(foo, "a", b, "c");

test/ast_checks/assert_args.txt

@@ -0,0 +1,4 @@
+./module/declaration/staticAssertDeclaration//assertArguments/unaryExpression[1]//identifierOrTemplateInstance/identifier[text()="foo"]
+./module/declaration/staticAssertDeclaration//assertArguments/unaryExpression[2]/primaryExpression/stringLiteral[text()='"a"']
+./module/declaration/staticAssertDeclaration//assertArguments/unaryExpression[3]//identifierOrTemplateInstance/identifier[text()="b"]
+./module/declaration/staticAssertDeclaration//assertArguments/unaryExpression[4]/primaryExpression/stringLiteral[text()='"c"']