rename _filename to fileName in function templates and closures, it's more useful

src/duk_builtin_error.c

@@ -153,7 +153,7 @@ int duk_builtin_error_prototype_stack(duk_context *ctx) {
 				pc = (int) fmod(d, DUK_DOUBLE_2TO32);
 				flags = (int) floor(d / DUK_DOUBLE_2TO32);
 				duk_get_prop_stridx(ctx, -2, DUK_STRIDX_NAME);
-				duk_get_prop_stridx(ctx, -3, DUK_STRIDX_INT_FILENAME);
+				duk_get_prop_stridx(ctx, -3, DUK_STRIDX_FILE_NAME);
 
 				duk_get_prop_stridx(ctx, -4, DUK_STRIDX_INT_PC2LINE);
 				if (duk_is_buffer(ctx, -1)) {

src/duk_js_compiler.c

@@ -837,14 +837,14 @@ static void convert_to_function_template(duk_compiler_ctx *comp_ctx) {
 		 */
 	}
 
-	/* _filename */
+	/* fileName */
 	if (comp_ctx->h_filename) {
 		/*
 		 *  Source filename (or equivalent), for identifying thrown errors.
 		 */
 
 		duk_push_hstring(ctx, comp_ctx->h_filename);
-		duk_def_prop_stridx(ctx, -2, DUK_STRIDX_INT_FILENAME, DUK_PROPDESC_FLAGS_NONE);
+		duk_def_prop_stridx(ctx, -2, DUK_STRIDX_FILE_NAME, DUK_PROPDESC_FLAGS_NONE);
 	}
 
 	/*

src/duk_js_var.c

@@ -113,10 +113,10 @@ void duk_js_push_closure(duk_hthread *thr,
 	duk_hcompiledfunction *fun_clos;
 	duk_u16 proplist[] = { DUK_STRIDX_INT_VARMAP,
 	                       DUK_STRIDX_INT_FORMALS,
-	                       DUK_STRIDX_INT_SOURCE,
 	                       DUK_STRIDX_NAME,
 	                       DUK_STRIDX_INT_PC2LINE,
-	                       DUK_STRIDX_INT_FILENAME };  /* order: most frequent to least frequent */
+	                       DUK_STRIDX_FILE_NAME,
+	                       DUK_STRIDX_INT_SOURCE };  /* order: most frequent to least frequent */
 	int i;
 	duk_u32 len_value;
 

src/genstrings.py

@@ -483,7 +483,8 @@ duk_string_list = [
 	mkstr("tracedata", custom=True),
 
 	# non-standard function instance properties
-	mkstr("name", custom=True),	# function declaration/expression name (or empty)
+	mkstr("name", custom=True), 	# function declaration/expression name (or empty)
+	mkstr("fileName", custom=True), # filename associated with function (shown in tracebacks)
 
 	# typeof - these produce unfortunate naming conflicts like "Object" vs "object"
 	mkstr("buffer", custom=True),
@@ -506,7 +507,6 @@ duk_string_list = [
 	mkstr("varenv", internal=True, custom=True),
 	mkstr("source", internal=True, custom=True),
 	mkstr("pc2line", internal=True, custom=True),
-	mkstr("filename", internal=True, custom=True),
 
 	# internal properties for thread objects