Implement the 'type' builtin (just the '-t' case), with tests.

Used by setup.sh in Nix.

Addresses issue #26.

core/builtin.py

@@ -58,7 +58,7 @@
 TRUE FALSE
 COLON
 TEST BRACKET
-HELP
+TYPE HELP
 """.split())
 
 
@@ -197,6 +197,9 @@ def Resolve(argv0):
   elif argv0 == "[":
     return EBuiltin.BRACKET
 
+  elif argv0 == "type":
+    return EBuiltin.TYPE
+
   elif argv0 == "help":
     return EBuiltin.HELP
 
@@ -646,6 +649,61 @@ def Unset(argv, mem, funcs):
   return 0
 
 
+TYPE_SPEC = _Register('type')
+TYPE_SPEC.ShortFlag('-t')
+
+def Type(argv, funcs, path_val):
+  arg, i = TYPE_SPEC.Parse(argv)
+
+  if path_val.tag == value_e.Str:
+    path_list = path_val.s.split(':')
+  else:
+    path_list = []  # treat as empty path
+
+  status = 0
+  if not arg.t:
+    util.warn("*** 'type' builtin called without -t ***")
+    status = 1
+    # Keep going anyway
+
+  for name in argv[i:]:
+    if name in funcs:
+      print('function')
+      continue
+
+    if Resolve(name) != EBuiltin.NONE:
+      print('builtin')
+      continue
+    if ResolveSpecial(name) != EBuiltin.NONE:
+      print('builtin')
+      continue
+    if lex.IsOtherBuiltin(name):
+      print('builtin')
+      continue
+
+    if lex.IsKeyword(name):
+      print('keyword')
+      continue
+
+    # Now look for files.
+    found = False
+    for path_dir in path_list:
+      full_path = os.path.join(path_dir, name)
+      if os.path.exists(full_path):
+        print('file')
+        found = True
+        break
+    if found:
+      continue
+
+    # Name not found.  Nothing printed, but status is 1.
+    #log('%r not found', name)
+    status = 1
+
+  return status
+
+
+
 def Trap(argv, traps):
   # TODO: register trap
 

core/cmd_exec.py

@@ -297,6 +297,10 @@ def _RunBuiltin(self, builtin_id, argv):
     elif builtin_id == EBuiltin.BRACKET:
       status = test_builtin.Test(argv, True)  # need_right_bracket
 
+    elif builtin_id == EBuiltin.TYPE:
+      path = self.mem.GetVar('PATH')
+      status = builtin.Type(argv, self.funcs, path)
+
     elif builtin_id == EBuiltin.HELP:
       loader = util.GetResourceLoader()
       status = builtin.Help(argv, loader)

osh/lex.py

@@ -181,7 +181,11 @@
   C('elif',     Id.KW_Elif),
   C('function', Id.KW_Function),
   C('time',     Id.KW_Time),
+]
 
+# These are treated like builtins in bash, but keywords in OSH.  However, we
+# main compatibility with bash for the 'type' builtin.
+_MORE_KEYWORDS = [
   C('declare',  Id.Assign_Declare),
   C('local',    Id.Assign_Local),
   C('readonly', Id.Assign_Readonly),
@@ -191,13 +195,27 @@
   C('return',   Id.ControlFlow_Return),
 ]
 
+
+_TYPE_KEYWORDS = set(name for _, name, _ in _KEYWORDS)
+_TYPE_KEYWORDS.add('{')  # not in our lexer list
+_TYPE_BUILTINS = set(name for _, name, _ in _MORE_KEYWORDS)
+
+
+def IsOtherBuiltin(name):
+  return name in _TYPE_BUILTINS
+
+
+def IsKeyword(name):
+  return name in _TYPE_KEYWORDS
+
+
 # These two can must be recognized in the OUTER state, but can't nested within
 # [[.
 # Keywords have to be checked before _UNQUOTED so we get <KW_If "if"> instead
 # of <Lit_Chars "if">.
 LEXER_DEF[LexMode.OUTER] = [
   C('((', Id.Op_DLeftParen),  # not allowed within [[
-] + _KEYWORDS + _UNQUOTED
+] + _KEYWORDS + _MORE_KEYWORDS + _UNQUOTED
 
 # DBRACKET: can be like OUTER, except:
 # - Don't really need redirects either... Redir_Less could be Op_Less

spec/builtin-type.test.sh

@@ -0,0 +1,27 @@
+#!/bin/bash
+#
+# Bash implements type -t.
+# 
+# NOTE: Aliases don't work in batch mode!  Interactive only.
+
+### type -t builtin -> function
+f() { echo hi; }
+type -t f
+# stdout-json: "function\n"
+
+### type -t builtin -> builtin
+type -t echo read : [ declare local break continue
+# stdout-json: "builtin\nbuiltin\nbuiltin\nbuiltin\nbuiltin\nbuiltin\nbuiltin\nbuiltin\n"
+
+### type -t builtin -> keyword
+type -t for time ! fi do {
+# stdout-json: "keyword\nkeyword\nkeyword\nkeyword\nkeyword\nkeyword\n"
+
+### type -t builtin -> file
+type -t find xargs
+# stdout-json: "file\nfile\n"
+
+### type -t builtin -> not found
+type -t echo ZZZ find =
+echo status=$?
+# stdout-json: "builtin\nfile\nstatus=1\n"

test/spec.sh

@@ -262,6 +262,12 @@ builtin-vars() {
     ${REF_SHELLS[@]} $OSH "$@"
 }
 
+# Bash impleement type -t, but no other shell does.  For Nix.
+builtin-type() {
+  sh-spec spec/builtin-type.test.sh \
+    $BASH $OSH "$@"
+}
+
 builtins-special() {
   sh-spec spec/builtins-special.test.sh --osh-failures-allowed 3 \
     ${REF_SHELLS[@]} $OSH "$@"