crystal-lang · Dec 3, 2016 · Dec 3, 2016
Showing with 34 additions and 13 deletions.

+1 −1 src/compiler/crystal/macros/methods.cr

+8 −1 src/compiler/crystal/semantic/call.cr

+11 −0 src/compiler/crystal/semantic/exception.cr

+14 −11 src/compiler/crystal/semantic/semantic_visitor.cr
diff --git a/src/compiler/crystal/macros/methods.cr b/src/compiler/crystal/macros/methods.cr
@@ -123,7 +123,7 @@ module Crystal
       end
       msg = msg.join " "
 
-      node.raise "can't expand macro: #{msg}"
+      node.raise msg, exception_type: MacroRaiseException
     end
 
     def interpret_run(node)

diff --git a/src/compiler/crystal/semantic/call.cr b/src/compiler/crystal/semantic/call.cr
@@ -926,7 +926,14 @@ class Crystal::Call
       yield
     rescue ex : Crystal::Exception
       if obj = @obj
-        raise "instantiating '#{obj.type}##{name}(#{args.map(&.type).join ", "})'", ex
+        if name == "initialize"
+          # Avoid putting 'initialize' in the error trace
+          # because it's most likely that this is happening
+          # inside a generated 'new' method
+          ::raise ex
+        else
+          raise "instantiating '#{obj.type}##{name}(#{args.map(&.type).join ", "})'", ex
+        end
       else
         raise "instantiating '#{name}(#{args.map(&.type).join ", "})'", ex
       end

diff --git a/src/compiler/crystal/semantic/exception.cr b/src/compiler/crystal/semantic/exception.cr
@@ -31,6 +31,14 @@ module Crystal
     end
 
     def initialize(message, @line, @column : Int32, @filename, @size, @inner = nil)
+      # If the inner exception is a macro raise, we replace this exception's
+      # message with that message. In this way the error message will
+      # look like a regular message produced by the compiler, and not
+      # because of an incorrect macro expansion.
+      if inner.is_a?(MacroRaiseException)
+        message = inner.message
+        @inner = nil
+      end
       super(message)
     end
 
@@ -283,6 +291,9 @@ module Crystal
   class UndefinedMacroMethodError < TypeException
   end
 
+  class MacroRaiseException < TypeException
+  end
+
   class Program
     def undefined_global_variable(node, similar_name)
       common = String.build do |str|

diff --git a/src/compiler/crystal/semantic/semantic_visitor.cr b/src/compiler/crystal/semantic/semantic_visitor.cr
@@ -221,10 +221,8 @@ abstract class Crystal::SemanticVisitor < Crystal::Visitor
   def expand_macro(node, raise_on_missing_const = true, first_pass = false)
     if expanded = node.expanded
       @exp_nest -= 1
-      begin
+      eval_macro(node) do
         expanded.accept self
-      rescue ex : Crystal::Exception
-        node.raise "expanding macro", ex
       end
       @exp_nest += 1
       return true
@@ -277,11 +275,10 @@ abstract class Crystal::SemanticVisitor < Crystal::Visitor
   end
 
   def expand_macro(the_macro, node, mode = nil)
-    begin
-      expanded_macro = yield
-    rescue ex : Crystal::Exception
-      node.raise "expanding macro", ex
-    end
+    expanded_macro =
+      eval_macro(node) do
+        yield
+      end
 
     mode ||= if @in_c_struct_or_union
                Program::MacroExpansionMode::Normal
@@ -353,10 +350,8 @@ abstract class Crystal::SemanticVisitor < Crystal::Visitor
 
   def expand_inline_macro(node, mode = nil)
     if expanded = node.expanded
-      begin
+      eval_macro(node) do
         expanded.accept self
-      rescue ex : Crystal::Exception
-        node.raise "expanding macro", ex
       end
       return expanded
     end
@@ -373,6 +368,14 @@ abstract class Crystal::SemanticVisitor < Crystal::Visitor
     generated_nodes
   end
 
+  def eval_macro(node)
+    yield
+  rescue ex : MacroRaiseException
+    node.raise ex.message, exception_type: MacroRaiseException
+  rescue ex : Crystal::Exception
+    node.raise "expanding macro", ex
+  end
+
   def check_valid_attributes(node, valid_attributes, desc)
     attributes = @attributes
     return unless attributes