Refactor to only touch ToSVisitor

spec/compiler/parser/parser_spec.cr

@@ -1118,7 +1118,7 @@ module Crystal
     it_parses "puts {{**1}}", Call.new(nil, "puts", MacroExpression.new(DoubleSplat.new(1.int32)))
     it_parses "{{a = 1 if 2}}", MacroExpression.new(If.new(2.int32, Assign.new("a".var, 1.int32)))
     it_parses "{% a = 1 %}", MacroExpression.new(Assign.new("a".var, 1.int32), output: false)
-    it_parses "{%\n  a = 1\n%}", MacroExpression.new(Assign.new("a".var, 1.int32), output: false, multiline: true)
+    it_parses "{%\n  a = 1\n%}", MacroExpression.new(Assign.new("a".var, 1.int32), output: false)
     it_parses "{% a = 1 if 2 %}", MacroExpression.new(If.new(2.int32, Assign.new("a".var, 1.int32)), output: false)
     it_parses "{% if 1; 2; end %}", MacroExpression.new(If.new(1.int32, 2.int32), output: false)
     it_parses "{%\nif 1; 2; end\n%}", MacroExpression.new(If.new(1.int32, 2.int32), output: false)
@@ -1128,8 +1128,8 @@ module Crystal
     it_parses "{% unless 1; 2; else 3; end %}", MacroExpression.new(Unless.new(1.int32, 2.int32, 3.int32), output: false)
     it_parses "{% unless 1\n  x\nend %}", MacroExpression.new(Unless.new(1.int32, "x".var), output: false)
     it_parses "{% x unless 1 %}", MacroExpression.new(Unless.new(1.int32, "x".var), output: false)
-    it_parses "{%\n  x unless 1\n%}", MacroExpression.new(Unless.new(1.int32, "x".var), output: false, multiline: true)
-    it_parses "{%\n  1\n  2\n  3\n%}", MacroExpression.new(Expressions.new([1.int32, 2.int32, 3.int32] of ASTNode), output: false, multiline: true)
+    it_parses "{%\n  x unless 1\n%}", MacroExpression.new(Unless.new(1.int32, "x".var), output: false)
+    it_parses "{%\n  1\n  2\n  3\n%}", MacroExpression.new(Expressions.new([1.int32, 2.int32, 3.int32] of ASTNode), output: false)
 
     assert_syntax_error "{% unless 1; 2; elsif 3; 4; end %}"
     assert_syntax_error "{% unless 1 %} 2 {% elsif 3 %} 3 {% end %}"

src/compiler/crystal/syntax/ast.cr

@@ -2187,32 +2187,24 @@ module Crystal
   end
 
   # A macro expression,
-  # surrounded by {{ ... }}` (output = true, multiline = false)
-  # or by `{% ... %}` (output = false, multiline = false)
-  #
-  # ```
-  # # (output = false, multiline = true)
-  # {%
-  #   ...
-  # %}
-  # ```
+  # surrounded by {{ ... }} (output = true)
+  # or by {% ... %} (output = false)
   class MacroExpression < ASTNode
     property exp : ASTNode
     property? output : Bool
-    property? multiline : Bool
 
-    def initialize(@exp : ASTNode, @output = true, @multiline : Bool = false)
+    def initialize(@exp : ASTNode, @output = true)
     end
 
     def accept_children(visitor)
       @exp.accept visitor
     end
 
     def clone_without_location
-      MacroExpression.new(@exp.clone, @output, @multiline)
+      MacroExpression.new(@exp.clone, @output)
     end
 
-    def_equals_and_hash exp, output?, multiline?
+    def_equals_and_hash exp, output?
   end
 
   # Free text that is part of a macro

src/compiler/crystal/syntax/parser.cr

@@ -3353,13 +3353,7 @@ module Crystal
 
     def parse_macro_control(start_location, macro_state = Token::MacroState.default)
       location = @token.location
-      next_token_skip_space
-      multiline = false
-
-      if @token.type.newline?
-        multiline = true
-        next_token_skip_space_or_newline
-      end
+      next_token_skip_space_or_newline
 
       case @token.value
       when Keyword::FOR
@@ -3446,7 +3440,7 @@ module Crystal
       exps = parse_expressions
       @in_macro_expression = false
 
-      MacroExpression.new(exps, output: false, multiline: multiline).at(location).at_end(token_end_location)
+      MacroExpression.new(exps, output: false).at(location).at_end(token_end_location)
     end
 
     def parse_macro_if(start_location, macro_state, check_end = true, is_unless = false)

src/compiler/crystal/syntax/to_s.cr

@@ -717,11 +717,11 @@ module Crystal
       end
       newline
 
-      @indent += 1
-      inside_macro do
-        accept node.body
+      with_indent do
+        inside_macro do
+          accept node.body
+        end
       end
-      @indent -= 1
 
       # newline
       append_indent
@@ -730,30 +730,34 @@ module Crystal
     end
 
     def visit(node : MacroExpression)
-      @str << (node.output? ? "{{ " : node.multiline? ? "{%" : "{% ")
+      # The node is considered multiline if its starting location is on a different line than its expression.
+      is_multiline = (start_loc = node.location) && (end_loc = node.exp.location) && end_loc.line_number > start_loc.line_number
+
+      @str << (node.output? ? "{{ " : is_multiline ? "{%" : "{% ")
 
-      if node.multiline?
+      if is_multiline
         newline
         @indent += 1
       end
 
       outside_macro do
-        # If the MacroExpression consists of a single node we need to manually handle appending indent and trailing newline if #multiline?
+        # If the MacroExpression consists of a single node we need to manually handle appending indent and trailing newline if *is_multiline*
         # Otherwise, the Expressions logic handles that for us
-        if node.multiline? && !node.exp.is_a?(Expressions)
+        if is_multiline && !node.exp.is_a?(Expressions)
           append_indent
         end
 
         node.exp.accept self
       end
 
-      if node.multiline?
+      # If the opening tag has a newline after it, force trailing tag to have one as well
+      if is_multiline
         @indent -= 1
         append_indent
         newline if !node.exp.is_a? Expressions
       end
 
-      @str << (node.output? ? " }}" : node.multiline? ? "%}" : " %}")
+      @str << (node.output? ? " }}" : is_multiline ? "%}" : " %}")
       false
     end
 
@@ -810,11 +814,11 @@ module Crystal
     def visit(node : MacroVerbatim)
       @str << "{% verbatim do %}"
 
-      @indent += 1
-      inside_macro do
-        node.exp.accept self
+      with_indent do
+        inside_macro do
+          node.exp.accept self
+        end
       end
-      @indent -= 1
 
       @str << "{% end %}"
       false