From 980bedc8a6e2180d60462204d54bbc1d4dd7c613 Mon Sep 17 00:00:00 2001
From: Barrett Ruth <br.barrettruth@gmail.com>
Date: Wed, 4 Feb 2026 23:51:15 -0500
Subject: [PATCH] fix(parser): emit hunks for files with unknown filetypes

Previously, hunks were discarded entirely if vim.filetype.match()
returned nil. This meant files with unrecognized extensions got no
highlighting at all - not even the basic green/red backgrounds for
added/deleted lines.

Remove the (current_lang or current_ft) condition from flush_hunk()
so all hunks are collected. highlight_hunk() already handles the
case where ft/lang are nil by skipping syntax highlighting but still
applying background colors.

Co-authored-by: phanen <phanen@qq.com>
---
 lua/diffs/parser.lua |  2 +-
 spec/parser_spec.lua | 19 +++++++++++++++++++
 2 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/lua/diffs/parser.lua b/lua/diffs/parser.lua
index bbb8ab5..da3b291 100644
--- a/lua/diffs/parser.lua
+++ b/lua/diffs/parser.lua
@@ -68,7 +68,7 @@ function M.parse_buffer(bufnr)
   local header_lines = {}
 
   local function flush_hunk()
-    if hunk_start and #hunk_lines > 0 and (current_lang or current_ft) then
+    if hunk_start and #hunk_lines > 0 then
       local hunk = {
         filename = current_filename,
         ft = current_ft,
diff --git a/spec/parser_spec.lua b/spec/parser_spec.lua
index 9d2c01b..5323d09 100644
--- a/spec/parser_spec.lua
+++ b/spec/parser_spec.lua
@@ -285,5 +285,24 @@ describe('parser', function()
       assert.are.equal('diff --git a/parser.lua b/parser.lua', hunks[1].header_lines[1])
       delete_buffer(bufnr)
     end)
+
+    it('emits hunk for files with unknown filetype', function()
+      local bufnr = create_buffer({
+        'M config.obscuretype',
+        '@@ -1,2 +1,3 @@',
+        ' setting1 = value1',
+        '-setting2 = value2',
+        '+setting2 = MODIFIED',
+        '+setting4 = newvalue',
+      })
+      local hunks = parser.parse_buffer(bufnr)
+
+      assert.are.equal(1, #hunks)
+      assert.are.equal('config.obscuretype', hunks[1].filename)
+      assert.is_nil(hunks[1].ft)
+      assert.is_nil(hunks[1].lang)
+      assert.are.equal(4, #hunks[1].lines)
+      delete_buffer(bufnr)
+    end)
   end)
 end)