zsh-workers/7636

6 files changed, 60 insertions, 31 deletions

diff --git a/Doc/Zsh/builtins.yo b/Doc/Zsh/builtins.yo
index 2f1f37258..0a1f917d4 100644
--- a/Doc/Zsh/builtins.yo
+++ b/Doc/Zsh/builtins.yo
@@ -440,7 +440,7 @@ added by explicit specification.  If has no effect if used with tt(-f).
 )
 alias(history)(fc -l)
 findex(integer)
-item(tt(integer) [ {tt(PLUS())|tt(-)}tt(glrtux) ] [ var(name)[tt(=)var(value)] ... ])(
+item(tt(integer) [ {tt(PLUS())|tt(-)}tt(ghlrtux) ] [ var(name)[tt(=)var(value)] ... ])(
 Equivalent to tt(typeset -i), except that options irrelevant to
 integers are not permitted.
 )
@@ -533,7 +533,7 @@ sitem([var(mm)tt(:)]var(ss))(minutes and seconds)
 endsitem()
 )
 findex(local)
-item(tt(local) [ {tt(PLUS())|tt(-)}tt(ALRUZailrtu) [var(n)]] [ var(name)[tt(=)var(value)] ] ...)(
+item(tt(local) [ {tt(PLUS())|tt(-)}tt(ALRUZahilrtu) [var(n)]] [ var(name)[tt(=)var(value)] ] ...)(
 Same as tt(typeset), except that the options tt(-g), tt(-x) and
 tt(-f) are not permitted.
 )
@@ -922,7 +922,7 @@ Equivalent to tt(whence -v).
 findex(typeset)
 cindex(parameters, setting)
 cindex(parameters, declaring)
-xitem(tt(typeset) [ {tt(PLUS())|tt(-)}tt(ALRUZafgilrtuxm) [var(n)]] [ \
+xitem(tt(typeset) [ {tt(PLUS())|tt(-)}tt(ALRUZafghilrtuxm) [var(n)]] [ \
 var(name)[tt(=)var(value)] ... ])
 item(tt(typeset) -T [ {tt(PLUS()|tt(-))}tt(LRUZrux) ] \
   var(SCALAR)[tt(=)var(value)] var(array))(
@@ -1038,6 +1038,24 @@ suppressed when the function is loaded.  The tt(fpath) parameter
 will be searched to find the function definition when the function
 is first referenced; see noderef(Functions).
 )
+item(tt(-h))(
+Hide: only useful for special parameters (those marked `<S>' in the table in
+ifzman(zmanref(zshparams))\
+ifnzman(noderef(Parameters))\
+), and for local parameters with the same name as a special parameter,
+though harmless for others.  A special parameter with this attribute will
+not retain its special effect when made local.  Thus after `tt(typeset -h
+PATH)', a function containing `tt(typeset PATH)' will create an ordinary
+local parameter without the usual behaviour of tt(PATH).  Alternatively,
+the local parameter may itself be given this attribute; hence inside a
+function `tt(typeset -h PATH)' creates an ordinary local parameter and the
+special tt(PATH) parameter is not altered in any way.  It is also possible
+to create a local parameter using `tt(typeset +h )var(special)', where the
+local copy of var(special) will retain its special properties regardless of
+having the tt(-h) attribute.  Global special parameters loaded from shell
+modules (currently those in tt(mapfile) and tt(parameter)) are
+automatically given the tt(-h) attribute to avoid name clashes.
+)
 item(tt(-i))(
 Use an internal integer representation.  If var(n) is nonzero it
 defines the output arithmetic base, otherwise it is determined by the
diff --git a/Doc/Zsh/params.yo b/Doc/Zsh/params.yo
index 65c8e7599..3b7857471 100644
--- a/Doc/Zsh/params.yo
+++ b/Doc/Zsh/params.yo
@@ -203,15 +203,17 @@ tt(unset) can be used to delete a parameter while it is still in scope;
 any outer parameter of the same name remains hidden.
 
 Special parameters may also be made local; they retain their special
-attributes.  This may have unexpected effects.  Firstly, there is no
-default value, so if there is no assigment at the point the variable is
-made local, it will be set to an empty value (or zero in the case of
-integers).  Secondly, special parameters which are made local will not be
-exported (as with other parameters), so that the global value of the
-parameter remains present in the environment if it is already there.  This
-should be particularly noted in the case of tt(PATH): the shell will use
-the local version of tt(PATH) for finding programmes, but programmes using
-the shell's environment will inherit the global version.  The following:
+attributes unless either the existing or the newly-created parameter
+has the tt(-h) (hide) attribute.  This may have unexpected effects.
+Firstly, there is no default value, so if there is no assigment at the
+point the variable is made local, it will be set to an empty value (or zero
+in the case of integers).  Secondly, special parameters which are made
+local will not be exported (as with other parameters), so that the global
+value of the parameter remains present in the environment if it is already
+there.  This should be particularly noted in the case of tt(PATH): the
+shell will use the local version of tt(PATH) for finding programmes, but
+programmes using the shell's environment will inherit the global version.
+The following:
 
 example(typeset PATH=/new/directory:$PATH)
 
diff --git a/Src/Modules/mapfile.c b/Src/Modules/mapfile.c
index a3386ed2e..cd9c0120d 100644
--- a/Src/Modules/mapfile.c
+++ b/Src/Modules/mapfile.c
@@ -87,7 +87,8 @@ createmapfilehash()
 	unsetparam_pm(pm, 0, 1);
     mapfile_pm = NULL;
 
-    if (!(pm = createparam(mapfile_nam, PM_SPECIAL|PM_REMOVABLE|PM_HASHED)))
+    if (!(pm = createparam(mapfile_nam,
+			   PM_SPECIAL|PM_HIDE|PM_REMOVABLE|PM_HASHED)))
 	return NULL;
 
     pm->level = pm->old ? locallevel : 0;
diff --git a/Src/Modules/parameter.c b/Src/Modules/parameter.c
index 2d932ce06..14f05d41d 100644
--- a/Src/Modules/parameter.c
+++ b/Src/Modules/parameter.c
@@ -47,7 +47,7 @@ createspecialhash(char *name, GetNodeFunc get, ScanTabFunc scan)
     Param pm;
     HashTable ht;
 
-    if (!(pm = createparam(name, PM_SPECIAL|PM_REMOVABLE|PM_HASHED)))
+    if (!(pm = createparam(name, PM_SPECIAL|PM_HIDE|PM_REMOVABLE|PM_HASHED)))
 	return NULL;
 
     pm->level = pm->old ? locallevel : 0;
diff --git a/Src/builtin.c b/Src/builtin.c
index 6a2ec8335..ed9d01909 100644
--- a/Src/builtin.c
+++ b/Src/builtin.c
@@ -50,7 +50,7 @@ static struct builtin builtins[] =
     BUILTIN("cd", 0, bin_cd, 0, 2, BIN_CD, NULL, NULL),
     BUILTIN("chdir", 0, bin_cd, 0, 2, BIN_CD, NULL, NULL),
     BUILTIN("continue", BINF_PSPECIAL, bin_break, 0, 1, BIN_CONTINUE, NULL, NULL),
-    BUILTIN("declare", BINF_TYPEOPTS | BINF_MAGICEQUALS | BINF_PSPECIAL, bin_typeset, 0, -1, 0, "ALRTUZafgilrtux", NULL),
+    BUILTIN("declare", BINF_TYPEOPTS | BINF_MAGICEQUALS | BINF_PSPECIAL, bin_typeset, 0, -1, 0, "ALRTUZafghilrtux", NULL),
     BUILTIN("dirs", 0, bin_dirs, 0, -1, 0, "v", NULL),
     BUILTIN("disable", 0, bin_enable, 0, -1, BIN_DISABLE, "afmr", NULL),
     BUILTIN("disown", 0, bin_fg, 0, -1, BIN_DISOWN, NULL, NULL),
@@ -60,7 +60,7 @@ static struct builtin builtins[] =
     BUILTIN("enable", 0, bin_enable, 0, -1, BIN_ENABLE, "afmr", NULL),
     BUILTIN("eval", BINF_PSPECIAL, bin_eval, 0, -1, BIN_EVAL, NULL, NULL),
     BUILTIN("exit", BINF_PSPECIAL, bin_break, 0, 1, BIN_EXIT, NULL, NULL),
-    BUILTIN("export", BINF_TYPEOPTS | BINF_MAGICEQUALS | BINF_PSPECIAL, bin_typeset, 0, -1, BIN_EXPORT, "LRTUZafilrtu", "xg"),
+    BUILTIN("export", BINF_TYPEOPTS | BINF_MAGICEQUALS | BINF_PSPECIAL, bin_typeset, 0, -1, BIN_EXPORT, "LRTUZafhilrtu", "xg"),
     BUILTIN("false", 0, bin_false, 0, -1, 0, NULL, NULL),
     BUILTIN("fc", BINF_FCOPTS, bin_fc, 0, -1, BIN_FC, "nlreIRWAdDfEim", NULL),
     BUILTIN("fg", 0, bin_fg, 0, -1, BIN_FG, NULL, NULL),
@@ -74,11 +74,11 @@ static struct builtin builtins[] =
 #endif
 
     BUILTIN("history", 0, bin_fc, 0, -1, BIN_FC, "nrdDfEim", "l"),
-    BUILTIN("integer", BINF_TYPEOPTS | BINF_MAGICEQUALS | BINF_PSPECIAL, bin_typeset, 0, -1, 0, "glrtux", "i"),
+    BUILTIN("integer", BINF_TYPEOPTS | BINF_MAGICEQUALS | BINF_PSPECIAL, bin_typeset, 0, -1, 0, "ghlrtux", "i"),
     BUILTIN("jobs", 0, bin_fg, 0, -1, BIN_JOBS, "dlpZrs", NULL),
     BUILTIN("kill", 0, bin_kill, 0, -1, 0, NULL, NULL),
     BUILTIN("let", 0, bin_let, 1, -1, 0, NULL, NULL),
-    BUILTIN("local", BINF_TYPEOPTS | BINF_MAGICEQUALS | BINF_PSPECIAL, bin_typeset, 0, -1, 0, "ALRTUZailrtu", NULL),
+    BUILTIN("local", BINF_TYPEOPTS | BINF_MAGICEQUALS | BINF_PSPECIAL, bin_typeset, 0, -1, 0, "ALRTUZahilrtu", NULL),
     BUILTIN("log", 0, bin_log, 0, 0, 0, NULL, NULL),
     BUILTIN("logout", 0, bin_break, 0, 1, BIN_LOGOUT, NULL, NULL),
 
@@ -97,7 +97,7 @@ static struct builtin builtins[] =
     BUILTIN("pwd", 0, bin_pwd, 0, 0, 0, "rLP", NULL),
     BUILTIN("r", BINF_R, bin_fc, 0, -1, BIN_FC, "nrl", NULL),
     BUILTIN("read", 0, bin_read, 0, -1, 0, "rzu0123456789pkqecnAlE", NULL),
-    BUILTIN("readonly", BINF_TYPEOPTS | BINF_MAGICEQUALS | BINF_PSPECIAL, bin_typeset, 0, -1, 0, "ALRTUZafgiltux", "r"),
+    BUILTIN("readonly", BINF_TYPEOPTS | BINF_MAGICEQUALS | BINF_PSPECIAL, bin_typeset, 0, -1, 0, "ALRTUZafghiltux", "r"),
     BUILTIN("rehash", 0, bin_hash, 0, 0, 0, "dfv", "r"),
     BUILTIN("return", BINF_PSPECIAL, bin_break, 0, 1, BIN_RETURN, NULL, NULL),
     BUILTIN("set", BINF_PSPECIAL, bin_set, 0, -1, 0, NULL, NULL),
@@ -111,7 +111,7 @@ static struct builtin builtins[] =
     BUILTIN("trap", BINF_PSPECIAL, bin_trap, 0, -1, 0, NULL, NULL),
     BUILTIN("true", 0, bin_true, 0, -1, 0, NULL, NULL),
     BUILTIN("type", 0, bin_whence, 0, -1, 0, "ampfsw", "v"),
-    BUILTIN("typeset", BINF_TYPEOPTS | BINF_MAGICEQUALS | BINF_PSPECIAL, bin_typeset, 0, -1, 0, "ALRTUZafgilrtuxm", NULL),
+    BUILTIN("typeset", BINF_TYPEOPTS | BINF_MAGICEQUALS | BINF_PSPECIAL, bin_typeset, 0, -1, 0, "ALRTUZafghilrtuxm", NULL),
     BUILTIN("umask", 0, bin_umask, 0, 1, 0, "S", NULL),
     BUILTIN("unalias", 0, bin_unhash, 1, -1, 0, "m", "a"),
     BUILTIN("unfunction", 0, bin_unhash, 1, -1, 0, "m", "f"),
@@ -1560,8 +1560,13 @@ typeset_single(char *cname, char *pname, Param pm, int func,
 	/*
 	 * If the original parameter was special and we're creating
 	 * a new one, we need to keep it special.
+	 *
+	 * The -h (hide) flags prevents an existing special being made
+	 * local.  It can be applied either to the special or in the
+	 * typeset/local statement for the local variable.
 	 */
-	newspecial = (pm->flags & PM_SPECIAL);
+	newspecial = (pm->flags & PM_SPECIAL)
+	    && !(on & PM_HIDE) && !(pm->flags & PM_HIDE & ~off);
 	usepm = 0;
     }
 
@@ -1780,7 +1785,7 @@ bin_typeset(char *name, char **argv, char *ops, int func)
     Param pm;
     Asgment asg;
     Patprog pprog;
-    char *optstr = "aiALRZlurtxUT";
+    char *optstr = "aiALRZlurtxUhT";
     int on = 0, off = 0, roff, bit = PM_ARRAY;
     int i;
     int returnval = 0, printflags = 0;
diff --git a/Src/zsh.h b/Src/zsh.h
index 3ba88cd83..3b5188724 100644
--- a/Src/zsh.h
+++ b/Src/zsh.h
@@ -1028,15 +1028,18 @@ struct param {
 #define PM_UNIQUE	(1<<11)	/* remove duplicates                        */
 #define PM_UNALIASED	(1<<11)	/* do not expand aliases when autoloading   */
 
-#define PM_TIED 	(1<<12)	/* array tied to colon-path or v.v.         */
-#define PM_LOCAL	(1<<13) /* this parameter will be made local        */
-#define PM_SPECIAL	(1<<14) /* special builtin parameter                */
-#define PM_DONTIMPORT	(1<<15)	/* do not import this variable              */
-#define PM_RESTRICTED	(1<<16) /* cannot be changed in restricted mode     */
-#define PM_UNSET	(1<<17)	/* has null value                           */
-#define PM_REMOVABLE	(1<<18)	/* special can be removed from paramtab     */
-#define PM_AUTOLOAD	(1<<19) /* autoloaded from module                   */
-#define PM_NORESTORE	(1<<20)	/* do not restore value of local special    */
+#define PM_HIDE		(1<<12)	/* Special behaviour hidden by local        */
+#define PM_TIED 	(1<<13)	/* array tied to colon-path or v.v.         */
+
+/* Remaining flags do not correspond directly to command line arguments */
+#define PM_LOCAL	(1<<14) /* this parameter will be made local        */
+#define PM_SPECIAL	(1<<15) /* special builtin parameter                */
+#define PM_DONTIMPORT	(1<<16)	/* do not import this variable              */
+#define PM_RESTRICTED	(1<<17) /* cannot be changed in restricted mode     */
+#define PM_UNSET	(1<<18)	/* has null value                           */
+#define PM_REMOVABLE	(1<<19)	/* special can be removed from paramtab     */
+#define PM_AUTOLOAD	(1<<20) /* autoloaded from module                   */
+#define PM_NORESTORE	(1<<21)	/* do not restore value of local special    */
 
 /* Flags for extracting elements of arrays and associative arrays */
 #define SCANPM_WANTVALS   (1<<0)