Gabriel Ivăncescu : jscript: Return undefined for empty RegExp captures in ES5+ mode.

[Alexandre Julliard]

Module: wine
Branch: master
Commit: 627e5b3bf1b4236a1eef35eeafb2ef44b7f96dd2
URL:    https://gitlab.winehq.org/wine/wine/-/commit/627e5b3bf1b4236a1eef35eeafb2ef4...

Author: Gabriel Ivăncescu 
Date:   Mon May 29 21:58:37 2023 +0300

jscript: Return undefined for empty RegExp captures in ES5+ mode.

Signed-off-by: Gabriel Ivăncescu

---

dlls/jscript/jsregexp.c      | 23 ++++++++++++++---------
 dlls/jscript/tests/regexp.js | 12 ++++++++++++
 dlls/mshtml/tests/es5.js     | 16 ++++++++++++++++
 3 files changed, 42 insertions(+), 9 deletions(-)

diff --git a/dlls/jscript/jsregexp.c b/dlls/jscript/jsregexp.c
index 3775df823c3..af96b63fe70 100644
--- a/dlls/jscript/jsregexp.c
+++ b/dlls/jscript/jsregexp.c
@@ -361,17 +361,22 @@ static HRESULT create_match_array(script_ctx_t *ctx, jsstr_t *input_str,
         return hres;

for(i=0; i < result->paren_count; i++) {
-        if(result->parens[i].index != -1)
-            str = jsstr_substr(input_str, result->parens[i].index, result->parens[i].length);
-        else
-            str = jsstr_empty();
-        if(!str) {
-            hres = E_OUTOFMEMORY;
-            break;
+        jsval_t val;
+
+        if(result->parens[i].index != -1) {
+            if(!(str = jsstr_substr(input_str, result->parens[i].index, result->parens[i].length))) {
+                hres = E_OUTOFMEMORY;
+                break;
+            }
+            val = jsval_string(str);
+        }else if(ctx->version < SCRIPTLANGUAGEVERSION_ES5) {
+            val = jsval_string(jsstr_empty());
+        }else {
+            val = jsval_undefined();
         }

-        hres = jsdisp_propput_idx(array, i+1, jsval_string(str));
-        jsstr_release(str);
+        hres = jsdisp_propput_idx(array, i+1, val);
+        jsval_release(val);
         if(FAILED(hres))
             break;
     }
diff --git a/dlls/jscript/tests/regexp.js b/dlls/jscript/tests/regexp.js
index 31b83216235..fb6ed0891d5 100644
--- a/dlls/jscript/tests/regexp.js
+++ b/dlls/jscript/tests/regexp.js
@@ -625,6 +625,18 @@ ok(tmp === "x*y", '"x/y".replace(/[/]/, "*") = ' + tmp);
 tmp = "x/y".replace(/[xy/]/g, "*");
 ok(tmp === "***", '"x/y".replace(/[xy/]/, "*") = ' + tmp);

+tmp = /()/.exec("")[1];
+ok(tmp === "", "/()/ captured: " + tmp);
+tmp = /()?/.exec("")[1];
+ok(tmp === "", "/()?/ captured: " + tmp);
+tmp = /()??/.exec("")[1];
+ok(tmp === "", "/()??/ captured: " + tmp);
+tmp = /()*/.exec("")[1];
+ok(tmp === "", "/()*/ captured: " + tmp);
+tmp = /()??()/.exec("");
+ok(tmp[1] === "", "/()??()/ [1] captured: " + tmp);
+ok(tmp[2] === "", "/()??()/ [2] captured: " + tmp);
+
 /(b)/.exec("abc");
 ok(RegExp.$1 === "b", "RegExp.$1 = " + RegExp.$1);
 ok("$2" in RegExp, "RegExp.$2 doesn't exist");
diff --git a/dlls/mshtml/tests/es5.js b/dlls/mshtml/tests/es5.js
index 982544f6b84..d466c1f9919 100644
--- a/dlls/mshtml/tests/es5.js
+++ b/dlls/mshtml/tests/es5.js
@@ -1610,6 +1610,22 @@ sync_test("isFrozen", function() {
     }
 });

+sync_test("RegExp", function() {
+    var r;
+
+    r = /()/.exec("")[1];
+    ok(r === "", "/()/ captured: " + r);
+    r = /()?/.exec("")[1];
+    ok(r === undefined, "/()?/ captured: " + r);
+    r = /()??/.exec("")[1];
+    ok(r === undefined, "/()??/ captured: " + r);
+    r = /()*/.exec("")[1];
+    ok(r === undefined, "/()*/ captured: " + r);
+    r = /()??()/.exec("");
+    ok(r[1] === undefined, "/()??()/ [1] captured: " + r);
+    ok(r[2] === "", "/()??()/ [2] captured: " + r);
+});
+
 sync_test("builtin_context", function() {
     var nullDisp = external.nullDisp;
     var tests = [