Revised TclFindElement() interface.

The final argument had been bracePtr, the address of a boolean var, where
the caller can be told whether or not the parsed list element was enclosed
in braces.  In practice, no callers really care about that.  What the callers
really want to know is whether the list element value exists as a literal
substring of the string being parsed, or whether a call to
TclCopyAndCollpase() is needed to produce the list element value.  Now the
final argument is changed to do what callers actually need.  This is a
better fit for the calls in tclParse.c, where now a good deal of
post-processing checking for "naked backslashes" is no longer necessary.
***POTENTIAL INCOMPATIBILITY***
For any callers calling in via the internal stubs table who really do use
the final argument explicitly to check for the enclosing brace scenario.
Simply looking for the braces where they must be is the revision available
to those callers, and it will backport cleanly.
Tests for expanded literals quoting detection.

1 files changed, 18 insertions, 24 deletions

diff --git a/generic/tclParse.c b/generic/tclParse.c
index 429d33a..4afb219 100644
--- a/generic/tclParse.c
+++ b/generic/tclParse.c
@@ -433,7 +433,7 @@ Tcl_ParseCommand(
 	    }
 
 	    if (isLiteral) {
-		int elemCount = 0, code = TCL_OK, nakedbs = 0;
+		int elemCount = 0, code = TCL_OK, literal = 1;
 		const char *nextElem, *listEnd, *elemStart;
 
 		/*
@@ -455,35 +455,26 @@ Tcl_ParseCommand(
 		 */
 
 		while (nextElem < listEnd) {
-		    int size, brace;
+		    int size;
 
 		    code = TclFindElement(NULL, nextElem, listEnd - nextElem,
-			    &elemStart, &nextElem, &size, &brace);
-		    if (code != TCL_OK) {
+			    &elemStart, &nextElem, &size, &literal);
+		    if ((code != TCL_OK) || !literal) {
 			break;
 		    }
-		    if (!brace) {
-			const char *s;
-
-			for(s=elemStart;size>0;s++,size--) {
-			    if ((*s)=='\\') {
-				nakedbs = 1;
-				break;
-			    }
-			}
-		    }
 		    if (elemStart < listEnd) {
 			elemCount++;
 		    }
 		}
 
-		if ((code != TCL_OK) || nakedbs) {
+		if ((code != TCL_OK) || !literal) {
 		    /*
-		     * Some list element could not be parsed, or contained
-		     * naked backslashes. This means the literal string was
-		     * not in fact a valid nor canonical list. Defer the
-		     * handling of this to compile/eval time, where code is
-		     * already in place to report the "attempt to expand a
+		     * Some list element could not be parsed, or is not
+		     * present as a literal substring of the script.  The
+		     * compiler cannot handle list elements that get generated
+		     * by a call to TclCopyAndCollapse(). Defer  the
+		     * handling of  this to  compile/eval time, where  code is
+		     * already  in place to  report the  "attempt to  expand a
 		     * non-list" error or expand lists that require
 		     * substitution.
 		     */
@@ -505,6 +496,7 @@ Tcl_ParseCommand(
 		     * tokens representing the expanded list.
 		     */
 
+		    CONST char *listStart;
 		    int growthNeeded = wordIndex + 2*elemCount
 			    - parsePtr->numTokens;
 
@@ -524,9 +516,9 @@ Tcl_ParseCommand(
 		     * word value.
 		     */
 
-		    nextElem = tokenPtr[1].start;
+		    listStart = nextElem = tokenPtr[1].start;
 		    while (nextElem < listEnd) {
-			int quoted, brace;
+			int quoted;
 	
 			tokenPtr->type = TCL_TOKEN_SIMPLE_WORD;
 			tokenPtr->numComponents = 1;
@@ -536,9 +528,11 @@ Tcl_ParseCommand(
 			tokenPtr->numComponents = 0;
 			TclFindElement(NULL, nextElem, listEnd - nextElem,
 				&(tokenPtr->start), &nextElem,
-				&(tokenPtr->size), &brace);
+				&(tokenPtr->size), NULL);
 
-			quoted = brace || tokenPtr->start[-1] == '"';
+			quoted = (tokenPtr->start[-1] == '{'
+				|| tokenPtr->start[-1] == '"')
+				&& tokenPtr->start > listStart;
 			tokenPtr[-1].start = tokenPtr->start - quoted;
 			tokenPtr[-1].size = tokenPtr->start + tokenPtr->size
 				- tokenPtr[-1].start + quoted;