Add heuristics for .h extension

autoload/polyglot.vim

@@ -154,6 +154,25 @@ func! polyglot#DetectAspFiletype()
   setf aspvbs | return
 endfunc
 
+func! polyglot#DetectHFiletype()
+  for lnum in range(1, min([line("$"), 200]))
+    let line = getline(lnum)
+    if line =~# '^\s*\(@\(interface\|class\|protocol\|property\|end\|synchronised\|selector\|implementation\)\(\<\|\>\)\|#import\s\+.\+\.h[">]\)'
+      if exists("g:c_syntax_for_h")
+        setf objc | return
+      endif
+      setf objcpp | return
+    endif
+  endfor
+  if exists("g:c_syntax_for_h")
+    setf c | return
+  endif
+  if exists("g:ch_syntax_for_h")
+    setf ch | return
+  endif
+  setf cpp | return
+endfunc
+
 func! polyglot#DetectMFiletype()
   let saw_comment = 0
   for lnum in range(1, min([line("$"), 100]))

autoload/sleuth.vim

@@ -10,7 +10,7 @@ let s:globs = {
   \ 'abc': '*.abc',
   \ 'abel': '*.abl',
   \ 'acedb': '*.wrm',
-  \ 'ada': '*.adb,*.ads,*.ada,*.gpr',
+  \ 'ada': '*.adb,*.ads,*.ada,*.adc,*.gpr,*.ada_m',
   \ 'ahdl': '*.tdf',
   \ 'aidl': '*.aidl',
   \ 'alsaconf': '',
@@ -34,17 +34,17 @@ let s:globs = {
   \ 'autoit': '*.au3',
   \ 'automake': '[Mm]akefile.am,GNUmakefile.am',
   \ 'ave': '*.ave',
-  \ 'awk': '*.awk',
+  \ 'awk': '*.awk,*.gawk',
   \ 'basic': '*.basic',
   \ 'blade': '*.blade,*.blade.php',
   \ 'brewfile': 'Brewfile',
-  \ 'c': '*.c,*.cats,*.h,*.idc',
+  \ 'c': '*.c,*.cats,*.h,*.idc,*.qc',
   \ 'caddyfile': 'Caddyfile',
   \ 'carp': '*.carp',
   \ 'clojure': '*.clj,*.boot,*.cl2,*.cljc,*.cljs,*.cljs.hl,*.cljscm,*.cljx,*.hic,*.edn,riemann.config,build.boot,profile.boot',
   \ 'cmake': '*.cmake,*.cmake.in,CMakeLists.txt',
   \ 'coffee': '*.coffee,*._coffee,*.cake,*.cjsx,*.iced,*.coffeekup,Cakefile',
-  \ 'cpp': '*.cpp,*.c++,*.cc,*.cp,*.cxx,*.h,*.h++,*.hh,*.hpp,*.hxx,*.inc,*.inl,*.ipp,*.tcc,*.tpp',
+  \ 'cpp': '*.cpp,*.c++,*.cc,*.cp,*.cxx,*.h,*.h++,*.hh,*.hpp,*.hxx,*.inc,*.inl,*.ipp,*.tcc,*.tpp,*.moc',
   \ 'cql': '*.cql',
   \ 'cryptol': '*.cry,*.cyl,*.lcry,*.lcyl',
   \ 'crystal': '*.cr,Projectfile',
@@ -52,7 +52,7 @@ let s:globs = {
   \ 'cucumber': '*.feature,*.story',
   \ 'cuesheet': '*.cue',
   \ 'd': '*.d,*.di',
-  \ 'dart': '*.dart',
+  \ 'dart': '*.dart,*.drt',
   \ 'dcov': '*.lst',
   \ 'dd': '*.dd',
   \ 'ddoc': '*.ddoc',