ash: fix . builtin

Also, move [[ ]] comment to test.c and expand it

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/coreutils/test.c b/coreutils/test.c
index cfaf4ca..73048d3 100644
--- a/coreutils/test.c
+++ b/coreutils/test.c
@@ -19,7 +19,6 @@
  * Original copyright notice states:
  *     "This program is in the Public Domain."
  */
-
 #include "libbb.h"
 #include <setjmp.h>
 
@@ -29,7 +28,6 @@
  * This is true regardless of PREFER_APPLETS and STANDALONE_SHELL
  * state. */
 
-
 /* test(1) accepts the following grammar:
 	oexpr	::= aexpr | aexpr "-o" oexpr ;
 	aexpr	::= nexpr | nexpr "-a" aexpr ;
@@ -47,6 +45,50 @@
 	operand ::= <any legal UNIX file name>
 */
 
+/* TODO: handle [[ expr ]] bashism bash-compatibly.
+ * [[ ]] is meant to be a "better [ ]", with less weird syntax
+ * and without the risk of variables and quoted strings misinterpreted
+ * as operators.
+ * This will require support from shells - we need to know quote status
+ * of each parameter (see below).
+ *
+ * Word splitting and pathname expansion should NOT be performed:
+ *      # a="a b"; [[ $a = "a b" ]] && echo YES
+ *      YES
+ *      # [[ /bin/m* ]] && echo YES
+ *      YES
+ *
+ * =~ should do regexp match
+ * = and == should do pattern match against right side:
+ *      # [[ *a* == bab ]] && echo YES
+ *      # [[ bab == *a* ]] && echo YES
+ *      YES
+ * != does the negated == (i.e., also with pattern matching).
+ * Pattern matching is quotation-sensitive:
+ *      # [[ bab == "b"a* ]] && echo YES
+ *      YES
+ *      # [[ bab == b"a*" ]] && echo YES
+ *
+ * Conditional operators such as -f must be unquoted literals to be recognized:
+ *      # [[ -e /bin ]] && echo YES
+ *      YES
+ *      # [[ '-e' /bin ]] && echo YES
+ *      bash: conditional binary operator expected...
+ *      # A='-e'; [[ $A /bin ]] && echo YES
+ *      bash: conditional binary operator expected...
+ *
+ * || and && should work as -o and -a work in [ ]
+ * -a and -o aren't recognized (&& and || are to be used instead)
+ * ( and ) do not need to be quoted unlike in [ ]:
+ *      # [[ ( abc ) && '' ]] && echo YES
+ *      # [[ ( abc ) || '' ]] && echo YES
+ *      YES
+ *      # [[ ( abc ) -o '' ]] && echo YES
+ *      bash: syntax error in conditional expression...
+ *
+ * Apart from the above, [[ expr ]] should work as [ expr ]
+ */
+
 #define TEST_DEBUG 0
 
 enum token {
diff --git a/shell/ash.c b/shell/ash.c
index 3452351..9b40ca3 100644
--- a/shell/ash.c
+++ b/shell/ash.c
@@ -2224,17 +2224,17 @@
 /* ============ Path search helper
  *
  * The variable path (passed by reference) should be set to the start
- * of the path before the first call; padvance will update
- * this value as it proceeds.  Successive calls to padvance will return
+ * of the path before the first call; path_advance will update
+ * this value as it proceeds.  Successive calls to path_advance will return
  * the possible path expansions in sequence.  If an option (indicated by
  * a percent sign) appears in the path entry then the global variable
  * pathopt will be set to point to it; otherwise pathopt will be set to
  * NULL.
  */
-static const char *pathopt;     /* set by padvance */
+static const char *pathopt;     /* set by path_advance */
 
 static char *
-padvance(const char **path, const char *name)
+path_advance(const char **path, const char *name)
 {
 	const char *p;
 	char *q;
@@ -2538,7 +2538,7 @@
 	}
 	do {
 		c = *path;
-		p = padvance(&path, dest);
+		p = path_advance(&path, dest);
 		if (stat(p, &statb) >= 0 && S_ISDIR(statb.st_mode)) {
 			if (c && c != ':')
 				flags |= CD_PRINT;
@@ -7159,7 +7159,7 @@
 		e = errno;
 	} else {
 		e = ENOENT;
-		while ((cmdname = padvance(&path, argv[0])) != NULL) {
+		while ((cmdname = path_advance(&path, argv[0])) != NULL) {
 			if (--idx < 0 && pathopt == NULL) {
 				tryexec(IF_FEATURE_SH_STANDALONE(-1,) cmdname, argv, envp);
 				if (errno != ENOENT && errno != ENOTDIR)
@@ -7198,7 +7198,7 @@
 	idx = cmdp->param.index;
 	path = pathval();
 	do {
-		name = padvance(&path, cmdp->cmdname);
+		name = path_advance(&path, cmdp->cmdname);
 		stunalloc(name);
 	} while (--idx >= 0);
 	out1fmt("%s%s\n", name, (cmdp->rehash ? "*" : nullstr));
@@ -7570,7 +7570,7 @@
 			p = command;
 		} else {
 			do {
-				p = padvance(&path, command);
+				p = path_advance(&path, command);
 				stunalloc(p);
 			} while (--j >= 0);
 		}
@@ -8727,23 +8727,6 @@
 #define BUILTIN_REG_ASSG        "6"
 #define BUILTIN_SPEC_REG_ASSG   "7"
 
-/* We do not handle [[ expr ]] bashism bash-compatibly,
- * we make it a synonym of [ expr ].
- * Basically, word splitting and pathname expansion should NOT be performed
- * Examples:
- * no word splitting:     a="a b"; [[ $a = "a b" ]]; echo $? should print "0"
- * no pathname expansion: [[ /bin/m* = "/bin/m*" ]]; echo $? should print "0"
- * Additional operators:
- * || and && should work as -o and -a
- * =~ regexp match
- * == should do _pattern match_ against right side. bash does this:
- *      # [[ *a* == bab ]] && echo YES
- *      # [[ bab == *a* ]] && echo YES
- *      YES
- * != does the negated == (i.e., also with pattern matching)
- * Apart from the above, [[ expr ]] should work as [ expr ]
- */
-
 /* Stubs for calling non-FAST_FUNC's */
 #if ENABLE_ASH_BUILTIN_ECHO
 static int FAST_FUNC echocmd(int argc, char **argv)   { return echo_main(argc, argv); }
@@ -9718,7 +9701,7 @@
 	setstackmark(&smark);
 	mpath = mpathset() ? mpathval() : mailval();
 	for (mtp = mailtime; mtp < mailtime + MAXMBOXES; mtp++) {
-		p = padvance(&mpath, nullstr);
+		p = path_advance(&mpath, nullstr);
 		if (p == NULL)
 			break;
 		if (*p == '\0')
@@ -11912,7 +11895,7 @@
 		goto try_cur_dir;
 	}
 
-	while ((fullname = padvance(&path, name)) != NULL) {
+	while ((fullname = path_advance(&path, name)) != NULL) {
  try_cur_dir:
 		if ((stat(fullname, &statb) == 0) && S_ISREG(statb.st_mode)) {
 			/*
@@ -11921,7 +11904,8 @@
 			 */
 			return fullname;
 		}
-		stunalloc(fullname);
+		if (fullname != name)
+			stunalloc(fullname);
 	}
 
 	/* not found in the PATH */
@@ -12095,7 +12079,7 @@
 	e = ENOENT;
 	idx = -1;
  loop:
-	while ((fullname = padvance(&path, name)) != NULL) {
+	while ((fullname = path_advance(&path, name)) != NULL) {
 		stunalloc(fullname);
 		/* NB: code below will still use fullname
 		 * despite it being "unallocated" */
diff --git a/shell/ash_test/ash-misc/source1.right b/shell/ash_test/ash-misc/source1.right
new file mode 100644
index 0000000..0ab7c54
--- /dev/null
+++ b/shell/ash_test/ash-misc/source1.right
@@ -0,0 +1,2 @@
+Sourced ok
+Done
diff --git a/shell/ash_test/ash-misc/source1.tests b/shell/ash_test/ash-misc/source1.tests
new file mode 100755
index 0000000..e2e75b2
--- /dev/null
+++ b/shell/ash_test/ash-misc/source1.tests
@@ -0,0 +1,5 @@
+echo "echo Sourced ok" >../sourced.sh
+PATH="..:$PATH"
+. sourced.sh
+rm ../sourced.sh
+echo Done
diff --git a/shell/ash_test/run-all b/shell/ash_test/run-all
index 4d0f39a..ad93e25 100755
--- a/shell/ash_test/run-all
+++ b/shell/ash_test/run-all
@@ -19,7 +19,7 @@
 do_test()
 {
     test -d "$1" || return 0
-    echo do_test "$1"
+#   echo do_test "$1"
     # $1 but with / replaced by # so that it can be used as filename part
     noslash=`echo "$1" | sed 's:/:#:g'`
     (
diff --git a/shell/hush.c b/shell/hush.c
index 245fb58..fe05e47 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -311,22 +311,9 @@
 #if ENABLE_HUSH_BASH_COMPAT
 # define CMD_SINGLEWORD_NOGLOB 2
 #endif
-// Basically, word splitting and pathname expansion should NOT be performed
-// Examples:
-// no word splitting:     a="a b"; [[ $a = "a b" ]]; echo $? should print "0"
-// no pathname expansion: [[ /bin/m* = "/bin/m*" ]]; echo $? should print "0"
-// Additional operators:
-// || and && should work as -o and -a
-// =~ regexp match
-// == should do _pattern match_ against right side. bash does this:
-//      # [[ *a* == bab ]] && echo YES
-//      # [[ bab == *a* ]] && echo YES
-//      YES
-// != does the negated == (i.e., also with pattern matching)
-// Apart from the above, [[ expr ]] should work as [ expr ]
 
 /* used for "export noglob=* glob* a=`echo a b`" */
-/*#define CMD_SINGLEWORD_NOGLOB_COND 3 */
+//#define CMD_SINGLEWORD_NOGLOB_COND 3
 // It is hard to implement correctly, it adds significant amounts of tricky code,
 // and all this is only useful for really obscure export statements
 // almost nobody would use anyway. #ifdef CMD_SINGLEWORD_NOGLOB_COND