From 20294968548a5d25d50c980181c21eb9199890bf Mon Sep 17 00:00:00 2001
From: Christopher Pickering <cpickering@rhc.net>
Date: Wed, 6 Oct 2021 15:41:21 +0200
Subject: [PATCH] simplified regex to improve speed

---
 src/djlint/formatter/compress_html.py | 39 ++-------------------------
 tests/test_django.py                  |  8 +++++-
 2 files changed, 9 insertions(+), 38 deletions(-)

diff --git a/src/djlint/formatter/compress_html.py b/src/djlint/formatter/compress_html.py
index 2a6f059..65c1405 100644
--- a/src/djlint/formatter/compress_html.py
+++ b/src/djlint/formatter/compress_html.py
@@ -82,28 +82,10 @@ def compress_html(html: str, config: Config) -> str:
 
     html = _strip_html_whitespace(html, config)
 
-    html = re.sub(
-        r"(<([\w]+)[^>]*>)\s+?(<\/\2>)",
-        r"\1\3",
-        html,
-        flags=re.IGNORECASE | re.MULTILINE,
-    )
-
-    # put empty template tags on one line
-    html = re.sub(
-        re.compile(
-            rf"({{%-?[ ]*?({config.start_template_tags})[^}}]+?-?%}})\s+?(\{{\%-?[ ]end\2[^}}]*?\%\}})",
-            flags=re.MULTILINE | re.IGNORECASE | re.VERBOSE,
-        ),
-        r"\1\3",
-        html,
-    )
-
     # put short single line tags on one line
-    # verbose doesn't seem to work with replace groups.
     html = re.sub(
         re.compile(
-            fr"(<({config.single_line_html_tags})>)\s*([^<\n]{{,80}})\s*?(</(\2)>)",
+            fr"(<({config.single_line_html_tags})(?:[^<>])*>)\s*([^<\n]{{,80}})\s*?(</(\2)>)",
             re.IGNORECASE | re.MULTILINE | re.DOTALL | re.VERBOSE,
         ),
         r"\1\3\4",
@@ -111,24 +93,7 @@ def compress_html(html: str, config: Config) -> str:
         re.IGNORECASE | re.MULTILINE | re.DOTALL,
     )
 
-    html = re.sub(
-        re.compile(
-            fr"(<({config.single_line_html_tags})>)\s*?([^<\n]{{,80}})\s*?(</(\2)>)",
-            re.IGNORECASE | re.MULTILINE | re.DOTALL | re.VERBOSE,
-        ),
-        r"\1\3\4",
-        html,
-    )
-
-    html = re.sub(
-        re.compile(
-            fr"(<({config.single_line_html_tags})[ ][^>\n]{{,80}}>)\s*([^<\n]{{,80}})\s*?(</(\2)>)",
-            re.IGNORECASE | re.MULTILINE | re.DOTALL | re.VERBOSE,
-        ),
-        r"\1\3\4",
-        html,
-    )
-
+    # put short template tags back on one line
     html = re.sub(
         re.compile(
             rf"({{%-?[ ]*?({config.single_line_template_tags})[^\n(?:%}})]{{,30}}%}})\s*([^%\n]{{,50}})\s*?({{%-?[ ]+?end(\2)[ ]*?%}})",
diff --git a/tests/test_django.py b/tests/test_django.py
index 7aaacd3..180c622 100644
--- a/tests/test_django.py
+++ b/tests/test_django.py
@@ -7,7 +7,7 @@ run::
 
 for a single test, run::
 
-   pytest tests/test_django.py::test_complex_attributes --cov=src/djlint \
+   pytest tests/test_django.py::test_empty_tags_on_one_line --cov=src/djlint \
      --cov-branch --cov-report xml:coverage.xml --cov-report term-missing
 
 """
@@ -20,6 +20,12 @@ from click.testing import CliRunner
 from .conftest import reformat
 
 
+def test_empty_tags_on_one_line(runner: CliRunner, tmp_file: TextIO) -> None:
+    output = reformat(tmp_file, runner, b"{% if stuff %}\n{% endif %}")
+    assert output["text"] == """{% if stuff %}{% endif %}\n"""
+    assert output["exit_code"] == 1
+
+
 def test_dj_comments_tag(runner: CliRunner, tmp_file: TextIO) -> None:
     output = reformat(
         tmp_file, runner, b"{# comment #}\n{% if this %}<div></div>{% endif %}"