Change to actually use POSIX extended regular expressions

as documented, not ECMAscript regexes (the default in C++ STL).

Note that this implies that '.' matches newlines.

Author: eldering

doc/format-spec.md

@@ -123,9 +123,12 @@ The following commands are available:
 <dt><tt>REGEX(&lt;value&gt; str [, &lt;variable&gt; name])</tt></dt>
 
 <dd>Match the extended regular expression 'str', which must be of
-    string type. Matching is performed greedily, while '.' (a dot)
-    does not match a newline. Optionally assign the matched string to
-    variable 'name'.</dd>
+    string type. Matching is performed greedily and '.' (a dot)
+    matches a newline, use <tt>[^\n]</tt> to work around this.
+    Optionally assign the matched string to variable 'name'. Note that
+    since some string characters have to be escaped already, you might
+    need to double escape them in a regex string. For example, to
+    match a literal backslash, enter <tt>\\\\</tt>.</dd>
 
 <dt><tt>ASSERT(&lt;test&gt; condition)</tt></dt>
 

libchecktestdata.cc

@@ -1089,7 +1089,7 @@ void checktoken(command cmd)
 
 	else if ( cmd.name()=="REGEX" ) {
 		string str = eval(cmd.args[0]).getstr();
-		regex regexstr(str);
+		regex regexstr(str,regex::extended);
 		match_results<string::const_iterator> res;
 		string matchstr;
 

tests/testprog23.in

@@ -1,3 +1,3 @@
 SET(foo="bar.*")
 STRING(foo) NEWLINE
-REGEX(foo) NEWLINE
+REGEX(foo) # Note that '.' also matches newlines and ERE is greedy.

tests/testprog25.in

@@ -1,2 +1,2 @@
 REGEX("\\\\(foo|(bar|baz))\
-x\n[\\.-\\}]") NEWLINE
+x\n[.-}]") NEWLINE

tests/testprog28.err

@@ -1,3 +1,4 @@
-REGEX(".*") NEWLINE
+# Note that ERE '.' also matches newlines!
+REGEX("[^\n]*") NEWLINE
 SET(a=1/2)
 ASSERT(a == 0.5)

tests/testprog28.in

@@ -1,3 +1,4 @@
-REGEX(".*") NEWLINE
+# Note that ERE '.' also matches newlines!
+REGEX("[^\n]*") NEWLINE
 SET(a=1/2.)
 ASSERT(a == 0.5)