From cf23af03ddea66427f940f407c1f921a255697a8 Mon Sep 17 00:00:00 2001
From: David Wessman <david.wesmn@gmail.com>
Date: Sun, 20 Aug 2023 08:36:20 +0200
Subject: [PATCH] Handles doctype more freely (#56)

- Support ERB-tags before DOCTYPE.
- Parse error on multiple DOCTYPE elements.
---
 CHANGELOG.md                   |  9 ++++++++-
 Gemfile.lock                   |  2 +-
 lib/syntax_tree/erb/parser.rb  | 18 +++++++++++++-----
 lib/syntax_tree/erb/version.rb |  2 +-
 test/html_test.rb              | 13 +++++++++++++
 5 files changed, 36 insertions(+), 8 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index daf96b5..9e5bfd9 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,12 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/) a
 
 ## [Unreleased]
 
+## [0.10.1] - 2023-08-20
+
+### Added
+
+- Allow `DOCTYPE` to be after other tags, to work with e.g. ERB-tags on first line.
+
 ## [0.10.0] - 2023-08-20
 
 - Changes how whitespace and newlines are handled.
@@ -70,7 +76,8 @@ Output:
 - Can format a lot of .html.erb-syntax and works as a plugin to syntax_tree.
 - This is still early and there are a lot of different weird syntaxes out there.
 
-[unreleased]: https://github.com/davidwessman/syntax_tree-erb/compare/v0.10.0...HEAD
+[unreleased]: https://github.com/davidwessman/syntax_tree-erb/compare/v0.10.1...HEAD
+[0.10.1]: https://github.com/davidwessman/syntax_tree-erb/compare/v0.10.0...v0.10.1
 [0.10.0]: https://github.com/davidwessman/syntax_tree-erb/compare/v0.9.5...v0.10.0
 [0.9.5]: https://github.com/davidwessman/syntax_tree-erb/compare/v0.9.4...v0.9.5
 [0.9.4]: https://github.com/davidwessman/syntax_tree-erb/compare/v0.9.3...v0.9.4
diff --git a/Gemfile.lock b/Gemfile.lock
index b97fdc9..0a32a37 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -1,7 +1,7 @@
 PATH
   remote: .
   specs:
-    w_syntax_tree-erb (0.10.0)
+    w_syntax_tree-erb (0.10.1)
       prettier_print (~> 1.2, >= 1.2.0)
       syntax_tree (~> 6.1, >= 6.1.1)
 
diff --git a/lib/syntax_tree/erb/parser.rb b/lib/syntax_tree/erb/parser.rb
index ed5aea4..3b02695 100644
--- a/lib/syntax_tree/erb/parser.rb
+++ b/lib/syntax_tree/erb/parser.rb
@@ -20,16 +20,16 @@ class MissingTokenError < ParseError
       def initialize(source)
         @source = source
         @tokens = make_tokens
+        @found_doctype = false
       end
 
       def parse
-        doctype = maybe { parse_doctype }
         elements = many { parse_any_tag }
 
         location =
           elements.first.location.to(elements.last.location) if elements.any?
 
-        Document.new(elements: [doctype].compact + elements, location: location)
+        Document.new(elements: elements, location: location)
       end
 
       def debug_tokens
@@ -44,11 +44,19 @@ def parse_any_tag
         loop do
           tag =
             atleast do
-              maybe { parse_html_comment } || maybe { parse_erb_tag } ||
-                maybe { parse_erb_comment } || maybe { parse_html_element } ||
-                maybe { parse_new_line } || maybe { parse_chardata }
+              maybe { parse_doctype } || maybe { parse_html_comment } ||
+                maybe { parse_erb_tag } || maybe { parse_erb_comment } ||
+                maybe { parse_html_element } || maybe { parse_new_line } ||
+                maybe { parse_chardata }
             end
 
+          if tag.is_a?(Doctype)
+            if @found_doctype
+              raise(ParseError, "Only one doctype element is allowed")
+            else
+              @found_doctype = true
+            end
+          end
           # Allow skipping empty CharData
           return tag unless tag.skip?
         end
diff --git a/lib/syntax_tree/erb/version.rb b/lib/syntax_tree/erb/version.rb
index b1ae2b5..a4e2d30 100644
--- a/lib/syntax_tree/erb/version.rb
+++ b/lib/syntax_tree/erb/version.rb
@@ -2,6 +2,6 @@
 
 module SyntaxTree
   module ERB
-    VERSION = "0.10.0"
+    VERSION = "0.10.1"
   end
 end
diff --git a/test/html_test.rb b/test/html_test.rb
index f97cb36..ca55327 100644
--- a/test/html_test.rb
+++ b/test/html_test.rb
@@ -34,6 +34,19 @@ def test_html_doctype
 
       parsed = ERB.parse("<!doctype html>")
       assert_instance_of(SyntaxTree::ERB::Doctype, parsed.elements.first)
+
+      # Allow doctype to not be the first element
+      parsed = ERB.parse("<% theme = \"general\" %> <!DOCTYPE html>")
+      assert_equal(2, parsed.elements.size)
+      assert_equal(
+        [SyntaxTree::ERB::ErbNode, SyntaxTree::ERB::Doctype],
+        parsed.elements.map(&:class)
+      )
+
+      # Do not allow multiple doctype elements
+      assert_raises(SyntaxTree::ERB::Parser::ParseError) do
+        ERB.parse("<!DOCTYPE html>\n<!DOCTYPE html>\n")
+      end
     end
 
     def test_html_comment