[PATCH v2 0/2] MR4109: jscript: Fix Array.map and Array.reduce when last element doesn't exist.

[Gabriel Ivăncescu (＠insn)]

--
  v2: jscript: Fix Array.reduce when last element doesn't exist.
      jscript: Fix Array.map when last element doesn't exist.

https://gitlab.winehq.org/wine/wine/-/merge_requests/4109

[PATCH v2 1/2] jscript: Fix Array.map when last element doesn't exist.

[Gabriel Ivăncescu]

From: Gabriel Ivăncescu

Signed-off-by: Gabriel Ivăncescu 
---
 dlls/jscript/array.c     | 14 ++++++++++----
 dlls/mshtml/tests/es5.js |  7 +++++++
 2 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/dlls/jscript/array.c b/dlls/jscript/array.c
index 48f665da576..f86a9323aa8 100644
--- a/dlls/jscript/array.c
+++ b/dlls/jscript/array.c
@@ -1330,9 +1330,9 @@ static HRESULT Array_map(script_ctx_t *ctx, jsval_t vthis, WORD flags, unsigned
 {
     jsval_t context_this = jsval_undefined();
     jsval_t callback_args[3], mapped_value;
+    UINT32 length, new_len, k;
     jsdisp_t *jsthis, *array;
     IDispatch *callback;
-    UINT32 length, k;
     HRESULT hres;

TRACE("\n");
@@ -1358,10 +1358,13 @@ static HRESULT Array_map(script_ctx_t *ctx, jsval_t vthis, WORD flags, unsigned
     if(FAILED(hres))
         goto done;

+    new_len = 0;
     for(k = 0; k < length; k++) {
         hres = jsdisp_get_idx(jsthis, k, &callback_args[0]);
-        if(hres == DISP_E_UNKNOWNNAME)
+        if(hres == DISP_E_UNKNOWNNAME) {
+            hres = S_OK;
             continue;
+        }
         if(FAILED(hres))
             break;

@@ -1375,12 +1378,15 @@ static HRESULT Array_map(script_ctx_t *ctx, jsval_t vthis, WORD flags, unsigned
         hres = jsdisp_propput_idx(array, k, mapped_value);
         if(FAILED(hres))
             break;
+        new_len = k + 1;
     }

-    if(SUCCEEDED(hres) && r)
+    if(SUCCEEDED(hres) && r) {
+        array_from_jsdisp(array)->length = new_len;
         *r = jsval_obj(array);
-    else
+    }else {
         jsdisp_release(array);
+    }
 done:
     jsdisp_release(jsthis);
     return hres;
diff --git a/dlls/mshtml/tests/es5.js b/dlls/mshtml/tests/es5.js
index 7e2f66daabf..fbcb1b42f3e 100644
--- a/dlls/mshtml/tests/es5.js
+++ b/dlls/mshtml/tests/es5.js
@@ -431,6 +431,13 @@ sync_test("array_map", function() {
     [1,2].map(function() {
         ok(this.valueOf() === 137, "this.valueOf() = " + this.valueOf());
     }, 137);
+
+    r = [1,,2,].map(function(x) { return "" + x; });
+    ok(r.length === 3, "[1,,2,].map length = " + r.length);
+    ok(r[0] === "1", "[1,,2,].map[0] = " + r[0]);
+    ok(r[2] === "2", "[1,,2,].map[2] = " + r[2]);
+    ok(!("1" in r), "[1,,2,].map[1] exists");
+    ok(!("3" in r), "[1,,2,].map[3] exists");
 });

sync_test("array_sort", function() {

[PATCH v2 2/2] jscript: Fix Array.reduce when last element doesn't exist.

[Gabriel Ivăncescu]

From: Gabriel Ivăncescu

Signed-off-by: Gabriel Ivăncescu 
---
 dlls/jscript/array.c     | 4 +++-
 dlls/mshtml/tests/es5.js | 3 +++
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/dlls/jscript/array.c b/dlls/jscript/array.c
index f86a9323aa8..29609526046 100644
--- a/dlls/jscript/array.c
+++ b/dlls/jscript/array.c
@@ -1426,8 +1426,10 @@ static HRESULT Array_reduce(script_ctx_t *ctx, jsval_t vthis, WORD flags, unsign

for(k = 0; k < length; k++) {
         hres = jsdisp_get_idx(jsthis, k, &callback_args[1]);
-        if(hres == DISP_E_UNKNOWNNAME)
+        if(hres == DISP_E_UNKNOWNNAME) {
+            hres = S_OK;
             continue;
+        }
         if(FAILED(hres))
             break;

diff --git a/dlls/mshtml/tests/es5.js b/dlls/mshtml/tests/es5.js
index fbcb1b42f3e..b6ce7be3c54 100644
--- a/dlls/mshtml/tests/es5.js
+++ b/dlls/mshtml/tests/es5.js
@@ -1336,6 +1336,9 @@ sync_test("reduce", function() {
     r = [1,2,3].reduce(function(a, value) { return a + value; }, "str");
     ok(r === "str123", "reduce() returned " + r);

+    r = [1,2,].reduce(function(a, value) { return a + value; }, "str");
+    ok(r === "str12", "reduce() returned " + r);
+
     array = [1,2,3];
     r = array.reduce(function(a, value, index, src) {
         ok(src === array, "src != array");

[Jacek Caban (＠jacek)]

Jacek Caban (@jacek) commented about dlls/jscript/array.c:
>      hres = jsdisp_propput_idx(array, k, mapped_value);
>      if(FAILED(hres))
>          break;
> -
>    new_len = k + 1;
> }
> - if(SUCCEEDED(hres) && r)
> - if(SUCCEEDED(hres) && r) {
> -
>    array_from_jsdisp(array)->length = new_len;

You could just pass 0 as length to `create_array` and `Array_on_put` will do the right thing.