Cleanup formcalc method generationchromium/3427

This CL simplifies the FormCalc method call generation when converted to
JavaScript. Currently we output the same chunk of code to run the
given method on an array or object per method call. This CL pulls out
the common execution code to a pfm_method_runner function which is used
instead.

An embedder test has been added to verify that method invocation from
formcalc works correctly.

Bug: chromium:814848
Change-Id: I1ec052eab051053fedcb464d57e0e15228b8c5a2
Reviewed-on: https://pdfium-review.googlesource.com/32372
Reviewed-by: Henrique Nakashima <hnakashima@chromium.org>
Commit-Queue: dsinclair <dsinclair@chromium.org>

3 files changed, 93 insertions, 64 deletions

diff --git a/xfa/fxfa/fm2js/cxfa_fmexpression.cpp b/xfa/fxfa/fm2js/cxfa_fmexpression.cpp
index a3c65a2203..ef2153d6be 100644
--- a/xfa/fxfa/fm2js/cxfa_fmexpression.cpp
+++ b/xfa/fxfa/fm2js/cxfa_fmexpression.cpp
@@ -89,6 +89,16 @@ bool CXFA_FMAST::ToJavaScript(CFX_WideTextBuf& js) {
   }
 
   js << L"(function() {\n";
+  js << L"let pfm_method_runner = function(obj, cb) {\n";
+  js << L"  if (pfm_rt.is_ary(obj)) {\n";
+  js << L"    let pfm_method_return = null;\n";
+  js << L"    for (var idx = obj.length -1; idx > 1; idx--) {\n";
+  js << L"      pfm_method_return = cb(obj[idx]);\n";
+  js << L"    }\n";
+  js << L"    return pfm_method_return;\n";
+  js << L"  }\n";
+  js << L"  return cb(obj);\n";
+  js << L"};\n";
   js << L"var pfm_ret = null;\n";
 
   for (const auto& expr : expressions_) {
@@ -100,7 +110,6 @@ bool CXFA_FMAST::ToJavaScript(CFX_WideTextBuf& js) {
 
   js << L"return pfm_rt.get_val(pfm_ret);\n";
   js << L"}).call(this);";
-
   return !CXFA_IsTooBig(js);
 }
 
diff --git a/xfa/fxfa/fm2js/cxfa_fmparser_unittest.cpp b/xfa/fxfa/fm2js/cxfa_fmparser_unittest.cpp
index 0dba59c3bb..81fae08384 100644
--- a/xfa/fxfa/fm2js/cxfa_fmparser_unittest.cpp
+++ b/xfa/fxfa/fm2js/cxfa_fmparser_unittest.cpp
@@ -42,6 +42,16 @@ TEST(CXFA_FMParserTest, CommentOnlyIsError) {
 TEST(CXFA_FMParserTest, CommentThenValue) {
   const wchar_t ret[] =
       L"(function() {\n"
+      L"let pfm_method_runner = function(obj, cb) {\n"
+      L"  if (pfm_rt.is_ary(obj)) {\n"
+      L"    let pfm_method_return = null;\n"
+      L"    for (var idx = obj.length -1; idx > 1; idx--) {\n"
+      L"      pfm_method_return = cb(obj[idx]);\n"
+      L"    }\n"
+      L"    return pfm_method_return;\n"
+      L"  }\n"
+      L"  return cb(obj);\n"
+      L"};\n"
       L"var pfm_ret = null;\n"
       L"pfm_ret = 12;\n"
       L"return pfm_rt.get_val(pfm_ret);\n"
@@ -75,6 +85,16 @@ TEST(CXFA_FMParserTest, Parse) {
 
   const wchar_t ret[] =
       L"(function() {\n"
+      L"let pfm_method_runner = function(obj, cb) {\n"
+      L"  if (pfm_rt.is_ary(obj)) {\n"
+      L"    let pfm_method_return = null;\n"
+      L"    for (var idx = obj.length -1; idx > 1; idx--) {\n"
+      L"      pfm_method_return = cb(obj[idx]);\n"
+      L"    }\n"
+      L"    return pfm_method_return;\n"
+      L"  }\n"
+      L"  return cb(obj);\n"
+      L"};\n"
       L"var pfm_ret = null;\n"
       L"if (pfm_rt.is_obj(this))\n{\n"
       L"pfm_rt.asgn_val_op(this, pfm_rt.Avg(pfm_rt.neg_op(3), 5, "
@@ -159,6 +179,16 @@ TEST(CXFA_FMParserTest, ParseFuncWithParams) {
 
   const wchar_t ret[] = {
       L"(function() {\n"
+      L"let pfm_method_runner = function(obj, cb) {\n"
+      L"  if (pfm_rt.is_ary(obj)) {\n"
+      L"    let pfm_method_return = null;\n"
+      L"    for (var idx = obj.length -1; idx > 1; idx--) {\n"
+      L"      pfm_method_return = cb(obj[idx]);\n"
+      L"    }\n"
+      L"    return pfm_method_return;\n"
+      L"  }\n"
+      L"  return cb(obj);\n"
+      L"};\n"
       L"var pfm_ret = null;\n"
       L"function MyFunction(param1, param2) {\n"
       L"var pfm_ret = null;\n"
@@ -187,6 +217,16 @@ TEST(CXFA_FMParserTest, ParseFuncWithoutParams) {
 
   const wchar_t ret[] = {
       L"(function() {\n"
+      L"let pfm_method_runner = function(obj, cb) {\n"
+      L"  if (pfm_rt.is_ary(obj)) {\n"
+      L"    let pfm_method_return = null;\n"
+      L"    for (var idx = obj.length -1; idx > 1; idx--) {\n"
+      L"      pfm_method_return = cb(obj[idx]);\n"
+      L"    }\n"
+      L"    return pfm_method_return;\n"
+      L"  }\n"
+      L"  return cb(obj);\n"
+      L"};\n"
       L"var pfm_ret = null;\n"
       L"function MyFunction() {\n"
       L"var pfm_ret = null;\n"
@@ -262,20 +302,22 @@ TEST(CXFA_FMParserTest, ParseCallSmall) {
   const wchar_t input[] = {L"i.f(O)"};
   const wchar_t ret[] = {
       L"(function() {\n"
-      L"var pfm_ret = null;\n"
-      L"pfm_ret = pfm_rt.get_val((function () {\n"
-      L"let pfm_cb = function(obj) {\n"
-      L"return obj.f(pfm_rt.get_val(O));\n"
+      L"let pfm_method_runner = function(obj, cb) {\n"
+      L"  if (pfm_rt.is_ary(obj)) {\n"
+      L"    let pfm_method_return = null;\n"
+      L"    for (var idx = obj.length -1; idx > 1; idx--) {\n"
+      L"      pfm_method_return = cb(obj[idx]);\n"
+      L"    }\n"
+      L"    return pfm_method_return;\n"
+      L"  }\n"
+      L"  return cb(obj);\n"
       L"};\n"
-      L"if (pfm_rt.is_ary(i)) {\n"
-      L"let method_return_value = null;\n"
-      L"for (var index = i.length - 1; index > 1; index--) {\n"
-      L"method_return_value = pfm_cb(i[index]);\n"
-      L"}\n"
-      L"return method_return_value;\n"
-      L"} else {\n"
-      L"return pfm_cb(i);\n"
-      L"}}).call(this));\n"
+      L"var pfm_ret = null;\n"
+      L"pfm_ret = pfm_rt.get_val((function() {\n"
+      L"  return pfm_method_runner(i, function(obj) {\n"
+      L"    return obj.f(pfm_rt.get_val(O));\n"
+      L"  });\n"
+      L"}).call(this));\n"
       L"return pfm_rt.get_val(pfm_ret);\n"
       L"}).call(this);"};
 
@@ -293,44 +335,30 @@ TEST(CXFA_FMParserTest, ParseCallBig) {
   const wchar_t input[] = {L"i.f(O.e(O.e(O)))"};
   const wchar_t ret[] = {
       L"(function() {\n"
-      L"var pfm_ret = null;\n"
-      L"pfm_ret = pfm_rt.get_val((function () {\n"
-      L"let pfm_cb = function(obj) {\n"
-      L"return obj.f(pfm_rt.get_val((function () {\n"
-      L"let pfm_cb = function(obj) {\n"
-      L"return obj.e(pfm_rt.get_val((function () {\n"
-      L"let pfm_cb = function(obj) {\n"
-      L"return obj.e(pfm_rt.get_val(O));\n"
-      L"};\n"
-      L"if (pfm_rt.is_ary(O)) {\n"
-      L"let method_return_value = null;\n"
-      L"for (var index = O.length - 1; index > 1; index--) {\n"
-      L"method_return_value = pfm_cb(O[index]);\n"
-      L"}\n"
-      L"return method_return_value;\n"
-      L"} else {\n"
-      L"return pfm_cb(O);\n"
-      L"}}).call(this)));\n"
+      L"let pfm_method_runner = function(obj, cb) {\n"
+      L"  if (pfm_rt.is_ary(obj)) {\n"
+      L"    let pfm_method_return = null;\n"
+      L"    for (var idx = obj.length -1; idx > 1; idx--) {\n"
+      L"      pfm_method_return = cb(obj[idx]);\n"
+      L"    }\n"
+      L"    return pfm_method_return;\n"
+      L"  }\n"
+      L"  return cb(obj);\n"
       L"};\n"
-      L"if (pfm_rt.is_ary(O)) {\n"
-      L"let method_return_value = null;\n"
-      L"for (var index = O.length - 1; index > 1; index--) {\n"
-      L"method_return_value = pfm_cb(O[index]);\n"
-      L"}\n"
-      L"return method_return_value;\n"
-      L"} else {\n"
-      L"return pfm_cb(O);\n"
-      L"}}).call(this)));\n"
-      L"};\n"
-      L"if (pfm_rt.is_ary(i)) {\n"
-      L"let method_return_value = null;\n"
-      L"for (var index = i.length - 1; index > 1; index--) {\n"
-      L"method_return_value = pfm_cb(i[index]);\n"
-      L"}\n"
-      L"return method_return_value;\n"
-      L"} else {\n"
-      L"return pfm_cb(i);\n"
-      L"}}).call(this));\n"
+      L"var pfm_ret = null;\n"
+      L"pfm_ret = pfm_rt.get_val((function() {\n"
+      L"  return pfm_method_runner(i, function(obj) {\n"
+      L"    return obj.f(pfm_rt.get_val((function() {\n"
+      L"  return pfm_method_runner(O, function(obj) {\n"
+      L"    return obj.e(pfm_rt.get_val((function() {\n"
+      L"  return pfm_method_runner(O, function(obj) {\n"
+      L"    return obj.e(pfm_rt.get_val(O));\n"
+      L"  });\n"
+      L"}).call(this)));\n"
+      L"  });\n"
+      L"}).call(this)));\n"
+      L"  });\n"
+      L"}).call(this));\n"
       L"return pfm_rt.get_val(pfm_ret);\n"
       L"}).call(this);"};
 
diff --git a/xfa/fxfa/fm2js/cxfa_fmsimpleexpression.cpp b/xfa/fxfa/fm2js/cxfa_fmsimpleexpression.cpp
index 069899311e..e34d4ba127 100644
--- a/xfa/fxfa/fm2js/cxfa_fmsimpleexpression.cpp
+++ b/xfa/fxfa/fm2js/cxfa_fmsimpleexpression.cpp
@@ -676,22 +676,14 @@ bool CXFA_FMMethodCallExpression::ToJavaScript(CFX_WideTextBuf& js,
   if (!m_pExp1->ToJavaScript(buf, ReturnType::kInfered))
     return false;
 
-  js << L"(function () {\n";
-  js << L"let pfm_cb = function(obj) {\n";
-  js << L"return obj.";
+  js << L"(function() {\n";
+  js << L"  return pfm_method_runner(" << buf << L", function(obj) {\n";
+  js << L"    return obj.";
   if (!m_pExp2->ToJavaScript(js, ReturnType::kInfered))
     return false;
   js << L";\n";
-  js << L"};\n";
-  js << L"if (pfm_rt.is_ary(" << buf << L")) {\n";
-  js << L"let method_return_value = null;\n";
-  js << L"for (var index = " << buf << L".length - 1; index > 1; index--) {\n";
-  js << L"method_return_value = pfm_cb(" << buf << L"[index]);\n";
-  js << L"}\n";
-  js << L"return method_return_value;\n";
-  js << L"} else {\n";
-  js << L"return pfm_cb(" << buf << L");\n";
-  js << L"}}).call(this)";
+  js << L"  });\n";
+  js << L"}).call(this)";
   return !CXFA_IsTooBig(js);
 }