[builtin/declare] Implement shopt -s extdebug format for declare -F

- Document it
- Tested with bin/osh build/py.sh - this now works!  task-five.sh uses
  extdebug.

Author: Andy C

build/py.sh

@@ -453,6 +453,7 @@ show-cpython-patches() {
   git diff 1d2b97384e14d65b1241f67fd995277f5508db28..HEAD Python-2.7.13/
 }
 
-if test $(basename $0) = 'py.sh'; then
+name=$(basename $0)
+if test "$name" = 'py.sh'; then
   task-five "$@"
 fi

builtin/assign_osh.py

@@ -16,6 +16,7 @@
 from core.error import e_usage
 from core import state
 from core import vm
+from display import ui
 from frontend import flag_util
 from frontend import args
 from mycpp.mylib import log, NewDict
@@ -27,7 +28,6 @@
 if TYPE_CHECKING:
     from core.state import Mem
     from core import optview
-    from display import ui
     from frontend.args import _Attributes
 
 _ = log
@@ -353,8 +353,17 @@ def _PrintFuncs(self, names):
         # type: (List[str]) -> int
         status = 0
         for name in names:
-            if self.procs.GetShellFunc(name):
-                print(name)
+            proc_val = self.procs.GetShellFunc(name)
+            if proc_val:
+                if self.exec_opts.extdebug():
+                    tok = proc_val.name_tok
+                    assert tok is not None, tok
+                    assert tok.line is not None, tok.line
+                    filename_str = ui.GetFilenameString(tok.line)
+                    line = '%s %s %s' % (name, tok.line.line_num, filename_str)
+                    print(line)
+                else:
+                    print(name)
                 # TODO: Could print LST for -f, or render LST.  Bash does this.  'trap'
                 # could use that too.
             else:

display/ui.py

@@ -154,6 +154,40 @@ def _PrintTokenTooLong(loc_tok, f):
     f.write(buf.getvalue())
 
 
+def GetFilenameString(line):
+    # type: (SourceLine) -> str
+    """Get the path of the file that a line appears in.
+
+    Returns "main" if it's stdin or -c
+    Returns "?" if it's not in a file.
+
+    Used by declare -F, with shopt -s extdebug.
+    """
+    src = line.src
+    UP_src = src
+
+    filename_str = '?'  # default
+    with tagswitch(src) as case:
+        # Copying bash, it uses the string 'main'.
+        # I think ? would be better here, because this can get confused with a
+        # file 'main'.  But it's fine for our task file usage.
+        if case(source_e.CFlag):
+            filename_str = 'main'
+        elif case(source_e.Stdin):
+            filename_str = 'main'
+
+        elif case(source_e.MainFile):
+            src = cast(source.MainFile, UP_src)
+            filename_str = src.path
+        elif case(source_e.OtherFile):
+            src = cast(source.OtherFile, UP_src)
+            filename_str = src.path
+
+        else:
+            pass
+    return filename_str
+
+
 def GetLineSourceString(line, quote_filename=False):
     # type: (SourceLine, bool) -> str
     """Returns a human-readable string for dev tools.

doc/ref/chap-option.md

@@ -89,13 +89,28 @@ called `-rf`.
 
 ## Debugging
 
-These options are from POSIX shell:
+<h3 id="xtrace">xtrace (-x)</h3>
 
-    xtrace   verbose
+Show execution traces.
 
-From bash:
+- In OSH, the [PS4][] variables control the display.
+- In YSH, the `SHX_*` variables control the display.
+
+[PS4]: chap-special-var.html#PS4
+
+This option is also `set -x`.  It's required by POSIX shell.
+
+### verbose
+
+Not implemented.
+
+This option is from POSIX shell.
+
+
+### extdebug
 
-    extdebug
+Show more info in when printing functions with `declare -f`.  Used by
+`task-five.sh`.
 
 ## Interactive
 

doc/ref/toc-osh.md

@@ -187,8 +187,8 @@ X [Unsupported]   enable
   [Errors]         nounset -u      errexit -e   inherit_errexit   pipefail
   [Globbing]       noglob -f       nullglob     failglob        X dotglob
                    dashglob (true)
-  [Other Option]   noclobber -C    errtrace -E
-  [Debugging]      xtrace        X verbose    X extdebug
+  [Other Option]   noclobber -C    errtrace -E 
+  [Debugging]      xtrace -x     X verbose      extdebug
   [Interactive]    emacs           vi
   [Compat]         eval_unsafe_arith            ignore_flags_not_impl
                    ignore_shopt_not_impl

frontend/option_def.py

@@ -218,7 +218,6 @@ def DoneWithImplementedOptions(self):
     'direxpand',
     'dirspell',
     'execfail',
-    'extdebug',  # for --debugger?
     'extquote',
     'force_fignore',
     'globasciiranges',
@@ -286,6 +285,8 @@ def _Init(opt_def):
     opt_def.Add('nocasematch')
     opt_def.Add('dotglob')
 
+    opt_def.Add('extdebug')  # for task files
+
     # recursive parsing and evaluation - for compatibility, ble.sh, etc.
     opt_def.Add('eval_unsafe_arith')
 

spec/assign-extended.test.sh

@@ -102,7 +102,23 @@ declare -f g
 add 7 main
 g 3 ROOT/spec/testdata/bash-source-2.sh
 ## END
-## N-I mksh stdout-json: ""
+## N-I mksh STDOUT:
+## END
+
+#### declare -F with shopt -s extdebug and main file
+case $SH in mksh) exit ;; esac
+
+$SH $REPO_ROOT/spec/testdata/extdebug.sh | sed "s;$REPO_ROOT;ROOT;g"
+
+## STDOUT:
+declare -f add
+declare -f g
+
+add 5 ROOT/spec/testdata/extdebug.sh
+g 3 ROOT/spec/testdata/bash-source-2.sh
+## END
+## N-I mksh STDOUT:
+## END
 
 #### declare -p var (exit status)
 var1() { echo func; }  # function names are NOT found.

spec/testdata/extdebug.sh

@@ -0,0 +1,12 @@
+source $REPO_ROOT/spec/testdata/bash-source-2.sh
+
+shopt -s extdebug
+
+add () { expr 4 + 4; }
+
+declare -F 
+echo
+
+declare -F add
+# in bash-source-2
+declare -F g | sed "s;$REPO_ROOT;ROOT;g"