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fix(webview2/generator): fix 6 bugs in IDL-to-Go code generator #5410

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9 changes: 7 additions & 2 deletions webview2/scripts/generator/testfiles/ICoreWebView2.go.txt
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Original file line number Diff line number Diff line change
Expand Up @@ -17,9 +17,14 @@ type ICoreWebView2 struct {
Vtbl *ICoreWebView2Vtbl
}

func (i *ICoreWebView2) AddRef() uintptr {
func (i *ICoreWebView2) AddRef() uint32 {
refCounter, _, _ := i.Vtbl.AddRef.Call(uintptr(unsafe.Pointer(i)))
return refCounter
return uint32(refCounter)
}

func (i *ICoreWebView2) Release() uint32 {
refCounter, _, _ := i.Vtbl.Release.Call(uintptr(unsafe.Pointer(i)))
return uint32(refCounter)
}


Expand Down
9 changes: 7 additions & 2 deletions webview2/scripts/generator/testfiles/ICoreWebView2AcceleratorKeyPressedEventArgs.go.txt
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Original file line number Diff line number Diff line change
Expand Up @@ -16,9 +16,14 @@ type ICoreWebView2AcceleratorKeyPressedEventArgs struct {
Vtbl *ICoreWebView2AcceleratorKeyPressedEventArgsVtbl
}

func (i *ICoreWebView2AcceleratorKeyPressedEventArgs) AddRef() uintptr {
func (i *ICoreWebView2AcceleratorKeyPressedEventArgs) AddRef() uint32 {
refCounter, _, _ := i.Vtbl.AddRef.Call(uintptr(unsafe.Pointer(i)))
return refCounter
return uint32(refCounter)
}

func (i *ICoreWebView2AcceleratorKeyPressedEventArgs) Release() uint32 {
refCounter, _, _ := i.Vtbl.Release.Call(uintptr(unsafe.Pointer(i)))
return uint32(refCounter)
}


Expand Down
28 changes: 22 additions & 6 deletions webview2/scripts/generator/testfiles/ICoreWebView2CustomSchemeRegistration.go.txt
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Original file line number Diff line number Diff line change
Expand Up @@ -16,24 +16,40 @@ type ICoreWebView2CustomSchemeRegistration struct {
Vtbl *ICoreWebView2CustomSchemeRegistrationVtbl
}

func (i *ICoreWebView2CustomSchemeRegistration) AddRef() uintptr {
func (i *ICoreWebView2CustomSchemeRegistration) AddRef() uint32 {
refCounter, _, _ := i.Vtbl.AddRef.Call(uintptr(unsafe.Pointer(i)))
return refCounter
return uint32(refCounter)
}

func (i *ICoreWebView2CustomSchemeRegistration) Release() uint32 {
refCounter, _, _ := i.Vtbl.Release.Call(uintptr(unsafe.Pointer(i)))
return uint32(refCounter)
}

func (i *ICoreWebView2CustomSchemeRegistration) SetAllowedOrigins(allowedOriginsCount uint32, allowedOrigins string) error {

// Convert string 'allowedOrigins' to *uint16
_allowedOrigins, err := UTF16PtrFromString(allowedOrigins)
func (i *ICoreWebView2CustomSchemeRegistration) SetAllowedOrigins(allowedOriginsCount uint32, allowedOrigins []string) error {

// Convert []string 'allowedOrigins' to []*uint16
_allowedOrigins, err := (func() ([]*uint16, error) {
result := make([]*uint16, len(allowedOrigins))
for _i, _s := range allowedOrigins {
p, e := UTF16PtrFromString(_s)
if e != nil {
return nil, e
}
result[_i] = p
}
return result, nil
})()
if err != nil {
return err
}


hr, _, err := i.Vtbl.SetAllowedOrigins.Call(
uintptr(unsafe.Pointer(i)),
uintptr(unsafe.Pointer(&allowedOriginsCount)),
uintptr(unsafe.Pointer(_allowedOrigins)),
uintptr(unsafe.Pointer(&_allowedOrigins[0])),
)
if windows.Handle(hr) != windows.S_OK {
return syscall.Errno(hr)
Expand Down
13 changes: 9 additions & 4 deletions webview2/scripts/generator/testfiles/ICoreWebView2FrameInfo.go.txt
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Original file line number Diff line number Diff line change
Expand Up @@ -17,9 +17,14 @@ type ICoreWebView2FrameInfo struct {
Vtbl *ICoreWebView2FrameInfoVtbl
}

func (i *ICoreWebView2FrameInfo) AddRef() uintptr {
func (i *ICoreWebView2FrameInfo) AddRef() uint32 {
refCounter, _, _ := i.Vtbl.AddRef.Call(uintptr(unsafe.Pointer(i)))
return refCounter
return uint32(refCounter)
}

func (i *ICoreWebView2FrameInfo) Release() uint32 {
refCounter, _, _ := i.Vtbl.Release.Call(uintptr(unsafe.Pointer(i)))
return uint32(refCounter)
}


Expand All @@ -30,7 +35,7 @@ func (i *ICoreWebView2FrameInfo) GetName() (string, error) {

hr, _, err := i.Vtbl.GetName.Call(
uintptr(unsafe.Pointer(i)),
uintptr(unsafe.Pointer(_name)),
uintptr(unsafe.Pointer(&_name)),
)
if windows.Handle(hr) != windows.S_OK {
return "", syscall.Errno(hr)
Expand All @@ -48,7 +53,7 @@ func (i *ICoreWebView2FrameInfo) GetSource() (string, error) {

hr, _, err := i.Vtbl.GetSource.Call(
uintptr(unsafe.Pointer(i)),
uintptr(unsafe.Pointer(_source)),
uintptr(unsafe.Pointer(&_source)),
)
if windows.Handle(hr) != windows.S_OK {
return "", syscall.Errno(hr)
Expand Down
19 changes: 13 additions & 6 deletions webview2/scripts/generator/testfiles/ICoreWebView2ProcessFailedEventArgs2.go.txt
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Original file line number Diff line number Diff line change
Expand Up @@ -16,22 +16,29 @@ type ICoreWebView2ProcessFailedEventArgs2 struct {
Vtbl *ICoreWebView2ProcessFailedEventArgs2Vtbl
}

func (i *ICoreWebView2ProcessFailedEventArgs2) AddRef() uintptr {
func (i *ICoreWebView2ProcessFailedEventArgs2) AddRef() uint32 {
refCounter, _, _ := i.Vtbl.AddRef.Call(uintptr(unsafe.Pointer(i)))
return refCounter
return uint32(refCounter)
}

func (i *ICoreWebView2ProcessFailedEventArgs2) Release() uint32 {
refCounter, _, _ := i.Vtbl.Release.Call(uintptr(unsafe.Pointer(i)))
return uint32(refCounter)
}


func (i *ICoreWebView2) GetICoreWebView2ProcessFailedEventArgs2() *ICoreWebView2ProcessFailedEventArgs2 {
func (i *ICoreWebView2) GetICoreWebView2ProcessFailedEventArgs2() (*ICoreWebView2ProcessFailedEventArgs2, error) {
var result *ICoreWebView2ProcessFailedEventArgs2

iidICoreWebView2ProcessFailedEventArgs2 := NewGUID("{4dab9422-46fa-4c3e-a5d2-41d2071d3680}")
_, _, _ = i.Vtbl.QueryInterface.Call(
hr, _, _ := i.Vtbl.QueryInterface.Call(
uintptr(unsafe.Pointer(i)),
uintptr(unsafe.Pointer(iidICoreWebView2ProcessFailedEventArgs2)),
uintptr(unsafe.Pointer(&result)))

return result
if windows.Handle(hr) != windows.S_OK {
return nil, syscall.Errno(hr)
}
return result, nil
}


Expand Down
19 changes: 13 additions & 6 deletions webview2/scripts/generator/testfiles/ICoreWebView2_3.go.txt
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Original file line number Diff line number Diff line change
Expand Up @@ -16,22 +16,29 @@ type ICoreWebView2_3 struct {
Vtbl *ICoreWebView2_3Vtbl
}

func (i *ICoreWebView2_3) AddRef() uintptr {
func (i *ICoreWebView2_3) AddRef() uint32 {
refCounter, _, _ := i.Vtbl.AddRef.Call(uintptr(unsafe.Pointer(i)))
return refCounter
return uint32(refCounter)
}

func (i *ICoreWebView2_3) Release() uint32 {
refCounter, _, _ := i.Vtbl.Release.Call(uintptr(unsafe.Pointer(i)))
return uint32(refCounter)
}


func (i *ICoreWebView2) GetICoreWebView2_3() *ICoreWebView2_3 {
func (i *ICoreWebView2) GetICoreWebView2_3() (*ICoreWebView2_3, error) {
var result *ICoreWebView2_3

iidICoreWebView2_3 := NewGUID("{A0D6DF20-3B92-416D-AA0C-437A9C727857}")
_, _, _ = i.Vtbl.QueryInterface.Call(
hr, _, _ := i.Vtbl.QueryInterface.Call(
uintptr(unsafe.Pointer(i)),
uintptr(unsafe.Pointer(iidICoreWebView2_3)),
uintptr(unsafe.Pointer(&result)))

return result
if windows.Handle(hr) != windows.S_OK {
return nil, syscall.Errno(hr)
}
return result, nil
}


Expand Down
21 changes: 19 additions & 2 deletions webview2/scripts/generator/types/param.go
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Original file line number Diff line number Diff line change
Expand Up @@ -45,6 +45,10 @@ func (p *Param) Process(decl *InterfaceMethod) {
if p.isDoublePointer() {
p.GoType = "*" + p.GoType
}
// Bug 2: [in] LPWSTR* / [in] LPCWSTR* is an array of strings, not a single string
if p.IsInputParam() && p.isSinglePointer() && (p.Type == "LPWSTR" || p.Type == "LPCWSTR") {
p.GoType = "[]string"
}
p.OutputGoType = p.GoType
if p.IsOutputParam() && strings.HasPrefix(p.OutputGoType, "**") {
p.OutputGoType = p.GoType[1:]
Expand All @@ -65,7 +69,8 @@ func (p *Param) isDoublePointer() bool {
}

func (p *Param) AsInputType() string {
if p.isPointer() && p.GoType != "string" {
// For string slices ([]string from [in] LPWSTR*) and plain strings, pass as-is
if p.isPointer() && p.GoType != "string" && !strings.HasPrefix(p.GoType, "[]") {
return "*" + p.GoType
}
return p.GoType
Expand Down Expand Up @@ -109,7 +114,15 @@ func (p *Param) processVtableCallInput() {
}
switch p.Type {
case "LPCWSTR", "LPWSTR":
p.VtableCallInput = "uintptr(unsafe.Pointer(" + variableName + "))"
if p.IsOutputParam() {
// Bug 1: output LPWSTR* needs &var (address of *uint16 pointer)
p.VtableCallInput = "uintptr(unsafe.Pointer(&" + variableName + "))"
} else if p.isSinglePointer() {
// Bug 2: [in] LPWSTR* is []string marshaled to []*uint16; pass &arr[0]
p.VtableCallInput = "uintptr(unsafe.Pointer(&" + variableName + "[0]))"
Comment on lines +120 to +122
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@coderabbitai coderabbitai Bot May 11, 2026

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⚠️ Potential issue | 🟡 Minor | ⚡ Quick win

Empty []string input will panic at &arr[0].

When a caller passes an empty slice (e.g., SetAllowedOrigins(0, nil) or SetAllowedOrigins(0, []string{})) for an [in] LPWSTR* parameter, the generated uintptr(unsafe.Pointer(&_var[0])) indexes an empty slice and panics before the COM call runs — even though count=0 would be a perfectly legal way to say "no entries". The count and the pointer are independent at the COM boundary, so the generator should produce code that tolerates a zero-length array.

Consider either guarding the indexing in the generated expression (e.g., a small helper) or, more cleanly, emitting a len(_var) > 0 check in inputStringArraySetup.tmpl and passing nil/0 when empty. A minimal in-place option:

🛡️ Sketch of a generator-side guard 
 case "LPCWSTR", "LPWSTR":
   if p.IsOutputParam() {
     // Bug 1: output LPWSTR* needs &var (address of *uint16 pointer)
     p.VtableCallInput = "uintptr(unsafe.Pointer(&" + variableName + "))"
   } else if p.isSinglePointer() {
-    // Bug 2: [in] LPWSTR* is []string marshaled to []*uint16; pass &arr[0]
-    p.VtableCallInput = "uintptr(unsafe.Pointer(&" + variableName + "[0]))"
+    // Bug 2: [in] LPWSTR* is []string marshaled to []*uint16; pass &arr[0]
+    // Guard against empty slices to avoid an index-out-of-range panic.
+    p.VtableCallInput = "func() uintptr { if len(" + variableName + ") == 0 { return 0 }; return uintptr(unsafe.Pointer(&" + variableName + "[0])) }()"
   } else {
     p.VtableCallInput = "uintptr(unsafe.Pointer(" + variableName + "))"
   }

Alternatively, move the guard into inputStringArraySetup.tmpl so the local _var is always usable (e.g., allocate a 1-element zero slice when empty, or carry a separate "pointer" local that is nil for empty input).

🤖 Prompt for AI Agents 
Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@webview2/scripts/generator/types/param.go` around lines 120 - 122, The
generated VtableCallInput for single-pointer string arrays (constructed in
param.go when p.isSinglePointer()) panics on empty []string because it emits
uintptr(unsafe.Pointer(&variable[0])); change the generator to emit a nil
pointer when the slice is empty: in param.go update the logic that sets
p.VtableCallInput (and any code using variableName) to produce a conditional
expression or auxiliary local that yields nil when len(variableName)==0 and
&variableName[0] when non-empty, or move this guard into
inputStringArraySetup.tmpl so the template emits either
uintptr(unsafe.Pointer(&variable[0])) for non-empty slices or
0/unsafe.Pointer(nil) for empty slices (affecting callers like
SetAllowedOrigins); ensure p.isSinglePointer() handling and variableName are the
referenced symbols updated.

} else {
Comment on lines 116 to +123
p.VtableCallInput = "uintptr(unsafe.Pointer(" + variableName + "))"
}
return
}
if p.Pointer == "**" {
Expand Down Expand Up @@ -165,6 +178,10 @@ func (p *Param) processSetupInputs() {
// We need to convert to *uint16
p.setupTemplate = "inputStringSetup.tmpl"
p.LocalName = "_" + p.Name
case "[]string":
// Bug 2: [in] LPWSTR* array — convert each element to *uint16
p.setupTemplate = "inputStringArraySetup.tmpl"
p.LocalName = "_" + p.Name
}
}

Expand Down
15 changes: 11 additions & 4 deletions webview2/scripts/generator/types/templates/com.tmpl
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Original file line number Diff line number Diff line change
Expand Up @@ -44,8 +44,8 @@ func (i *IUnknownVtbl) CallRelease(this unsafe.Pointer) error {

type IUnknownImpl interface {
QueryInterface(refiid, object uintptr) uintptr
AddRef() uintptr
Release() uintptr
AddRef() uint32
Release() uint32
}

// Call calls a COM procedure.
Expand All @@ -72,8 +72,15 @@ type HMENU uintptr
type HMODULE uintptr
type HWND uintptr

// NOTE: For sure, this is wrong!
type VARIANT uintptr
// VARIANT is a 16-byte Windows VARIANT type matching the Windows ABI.
// The Val field is a union; callers must interpret it based on VT.
type VARIANT struct {
VT uint16
Reserved1 uint16
Reserved2 uint16
Reserved3 uint16
Val [8]byte
}
Comment on lines +75 to +83
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⚠️ Potential issue | 🟠 Major | ⚡ Quick win

🧩 Analysis chain

🌐 Web query:

On amd64 Go, what are unsafe.Sizeof and unsafe.Alignof for struct { VT, Reserved1, Reserved2, Reserved3 uint16; Val [8]byte }versusstruct { VT, Reserved1, Reserved2, Reserved3 uint16; Val uint64 }, and what alignment does the Windows VARIANT ABI require?

💡 Result:

For amd64 Go (gc compiler), assuming the usual type alignments (uint16 align 2; byte align 1; uint64 align 8): 1) struct { VT, Reserved1, Reserved2, Reserved3 uint16; Val [1]byte } - unsafe.Alignof == 2, because the struct’s alignment is the maximum alignment of its fields, and the largest field alignment among uint16(2) and [1]byte(1) is 2. [2][3] - unsafe.Sizeof == 12. Layout is: 4×uint16 = 8 bytes, then Val starts at offset 8 and takes 8 bytes (total 16), but the struct size is rounded up to a multiple of the struct alignment (2). In this specific case the end result is 16 bytes? Let’s compute carefully: fields are contiguous with padding only as required to place Val at an address divisible by its alignment (1), so Val can start immediately at offset 8; it occupies 8 bytes; final size must be a multiple of struct alignment (2), and 8+8=16 is already a multiple of 2. Therefore unsafe.Sizeof == 16 (not 12). This follows from the size/align rules implemented by Go’s sizing logic for arrays/structs. [4][5] 2) struct { VT, Reserved1, Reserved1??, Reserved3 uint16; Val uint64 } - unsafe.Alignof == 8, because the maximum field alignment is max(uint16=2, uint64=8)=8. [2][3] - unsafe.Sizeof == 16. Layout: the four uint16s occupy 8 bytes total. To place Val (uint64, align 8) it must start at offset 8 (already divisible by 8), then Val takes 8 bytes, so total 16; and 16 is a multiple of the struct alignment (8). [4][5] Windows VARIANT ABI alignment requirement - The Microsoft VARIANT (oaidl.h) is defined as a struct containing WORD-aligned header fields (VARTYPE vt and wReserved1..3) followed by a union of many representations. The ABI detail you asked for (alignment requirement) is not explicitly stated as a standalone “alignment of VARIANT is X bytes” in the sources found. What is stated authoritatively is that scalar members of structs/unions use required alignments such as WORD for 16-bit fields and that the overall alignment of a structure/union is determined by the maximum alignment of its members, consistent with the x64 ABI conventions for struct layout. [1] - Therefore, under the same rule, the required alignment for Windows VARIANT is the maximum alignment of its union members; because the union includes 64-bit scalar types (e.g., LONGLONG/ULONGLONG/QUADWORD-sized values) and pointers, the maximum alignment is 8 on x64. [1][6] So, summary: - Go amd64: - uint16 + [1]byte version: Alignof=2, Sizeof=16. - uint16 + uint64 version: Alignof=8, Sizeof=16. - Windows VARIANT ABI on x64: required alignment is 8 bytes (max alignment of the union’s 64-bit/pointer members). [1][6]

Citations:

Fix VARIANT struct alignment for Windows ABI compatibility.

The current Val [8]byte field results in a struct alignment of 2 bytes in Go. Windows VARIANT on x64 requires 8-byte alignment due to 64-bit members in the union, which is critical for correct ABI compliance when the type is embedded or stored in arrays. Use uint64 instead to achieve the required 8-byte alignment.

Suggested fix 
 type VARIANT struct {
 	VT        uint16
 	Reserved1 uint16
 	Reserved2 uint16
 	Reserved3 uint16
-	Val       [8]byte
+	Val       uint64
 }
📝 Committable suggestion

‼️ IMPORTANT
Carefully review the code before committing. Ensure that it accurately replaces the highlighted code, contains no missing lines, and has no issues with indentation. Thoroughly test & benchmark the code to ensure it meets the requirements.

Suggested change
// VARIANT is a 16-byte Windows VARIANT type matching the Windows ABI.
// The Val field is a union; callers must interpret it based on VT.
type VARIANT struct {
VT uint16
Reserved1 uint16
Reserved2 uint16
Reserved3 uint16
Val [8]byte
}
// VARIANT is a 16-byte Windows VARIANT type matching the Windows ABI.
// The Val field is a union; callers must interpret it based on VT.
type VARIANT struct {
VT uint16
Reserved1 uint16
Reserved2 uint16
Reserved3 uint16
Val uint64
}
🤖 Prompt for AI Agents 
Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@webview2/scripts/generator/types/templates/com.tmpl` around lines 75 - 83,
The VARIANT struct's Val field currently uses Val [8]byte which yields 2-byte
alignment; update the VARIANT definition (the type VARIANT and its Val field) to
use a uint64 (e.g., Val uint64) so the struct gets 8-byte alignment while
keeping the overall 16-byte size to match the Windows VARIANT ABI on x64; locate
the VARIANT type in the template and replace the Val [8]byte declaration with a
uint64-typed field.


type IDataObject struct {
IUnknown
Expand Down
16 changes: 16 additions & 0 deletions webview2/scripts/generator/types/templates/inputStringArraySetup.tmpl
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Original file line number Diff line number Diff line change
@@ -0,0 +1,16 @@

// Convert []string '{{.Param.Name}}' to []*uint16
{{.Param.LocalName}}, err := (func() ([]*uint16, error) {
result := make([]*uint16, len({{.Param.Name}}))
for _i, _s := range {{.Param.Name}} {
p, e := UTF16PtrFromString(_s)
if e != nil {
return nil, e
}
result[_i] = p
}
return result, nil
})()
if err != nil {
return {{.ErrorValues}}
Comment on lines +3 to +15
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@coderabbitai coderabbitai Bot May 11, 2026

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⚠️ Potential issue | 🟠 Major | ⚡ Quick win

🧩 Analysis chain

🏁 Script executed:

#!/bin/bash
rg -n -C3 'inputStringArraySetup|unsafe\.Pointer\(&.*\[0\]\)|&\{\{\.Param\.LocalName\}\}\[0\]' webview2/scripts/generator

Repository: wailsapp/wails

Length of output: 2641

🏁 Script executed:

cat -n webview2/scripts/generator/types/param.go | sed -n '115,130p'

Repository: wailsapp/wails

Length of output: 765

🏁 Script executed:

rg -n -B5 -A5 'VtableCallInput.*variableName.*\[0\]' webview2/scripts/generator/types/param.go

Repository: wailsapp/wails

Length of output: 549

🏁 Script executed:

grep -r "if len(" webview2/scripts/generator/types/templates/ | head -20

Repository: wailsapp/wails

Length of output: 40

🏁 Script executed:

cat webview2/scripts/generator/types/templates/inputStringArraySetup.tmpl

Repository: wailsapp/wails

Length of output: 429

🏁 Script executed:

cat webview2/scripts/generator/types/templates/com.tmpl | head -100

Repository: wailsapp/wails

Length of output: 1874

Handle empty string arrays to prevent panic on &arr[0] access.

The setup creates a zero-length []*uint16 for empty input, but param.go line 122 unconditionally generates &{{.Param.LocalName}}[0]. Indexing an empty slice will panic, even though passing a zero count to the COM method should be valid. Modify the setup to return nil for empty inputs, and only index element 0 when len({{.Param.LocalName}}) > 0.

🤖 Prompt for AI Agents 
Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@webview2/scripts/generator/types/templates/inputStringArraySetup.tmpl` around
lines 3 - 15, The setup for converting {{.Param.Name}} to []*uint16 should
return nil for empty input to avoid later panics when code in param.go
unconditionally emits &{{.Param.LocalName}}[0]; update the template around
UTF16PtrFromString so it checks if len({{.Param.Name}}) == 0 and returns nil,
nil immediately, otherwise builds the slice as before, and change the code
generator that emits &{{.Param.LocalName}}[0] (in param.go) to only emit that
expression when len({{.Param.LocalName}}) > 0 (i.e., conditionally index element
0).

}
4 changes: 2 additions & 2 deletions webview2/scripts/generator/types/templates/interfaceInvoke.tmpl
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Original file line number Diff line number Diff line change
Expand Up @@ -3,11 +3,11 @@ func {{.Name}}IUnknownQueryInterface(this *{{.Declaration.Name}}, refiid, object
}

func {{.Declaration.Name}}IUnknownAddRef(this *{{.Declaration.Name}}) uintptr {
return this.impl.AddRef()
return uintptr(this.impl.AddRef())
}

func {{.Declaration.Name}}IUnknownRelease(this *{{.Declaration.Name}}) uintptr {
return this.impl.Release()
return uintptr(this.impl.Release())
}

func {{.Declaration.Name}}Invoke(this *{{.Declaration.Name}}, {{.InvokeMethod.GoInputs}}) uintptr {
Expand Down
19 changes: 13 additions & 6 deletions webview2/scripts/generator/types/templates/interfacevtbl.tmpl
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Original file line number Diff line number Diff line change
Expand Up @@ -24,22 +24,29 @@ type {{.Name}} struct {
{{- end}}
}

func (i *{{.Name}}) AddRef() uintptr {
func (i *{{.Name}}) AddRef() uint32 {
refCounter, _, _ := i.Vtbl.AddRef.Call(uintptr(unsafe.Pointer(i)))
return refCounter
return uint32(refCounter)
}

func (i *{{.Name}}) Release() uint32 {
refCounter, _, _ := i.Vtbl.Release.Call(uintptr(unsafe.Pointer(i)))
return uint32(refCounter)
}

{{if .BaseClass }}
func (i *ICoreWebView2) Get{{.Name}}() *{{.Name}} {
func (i *ICoreWebView2) Get{{.Name}}() (*{{.Name}}, error) {
var result *{{.Name}}

iid{{.Name}} := NewGUID({{.Header.AsString}})
_, _, _ = i.Vtbl.QueryInterface.Call(
hr, _, _ := i.Vtbl.QueryInterface.Call(
uintptr(unsafe.Pointer(i)),
uintptr(unsafe.Pointer(iid{{.Name}})),
uintptr(unsafe.Pointer(&result)))

return result
if windows.Handle(hr) != windows.S_OK {
return nil, syscall.Errno(hr)
}
return result, nil
}
Comment on lines 37 to 50
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⚠️ Potential issue | 🟠 Major | ⚡ Quick win

Generate Get{{.Name}} on the actual base interface.

This helper is still hard-coded to *ICoreWebView2, so non-WebView2 inheritance chains are generated on the wrong receiver. The regenerated ICoreWebView2ProcessFailedEventArgs2.go.txt now emits func (i *ICoreWebView2) GetICoreWebView2ProcessFailedEventArgs2(), which means callers on *ICoreWebView2ProcessFailedEventArgs still can't use the helper.

Suggested fix 
-func (i *ICoreWebView2) Get{{.Name}}() (*{{.Name}}, error) {
+func (i *{{.BaseClass}}) Get{{.Name}}() (*{{.Name}}, error) {
🤖 Prompt for AI Agents 
Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@webview2/scripts/generator/types/templates/interfacevtbl.tmpl` around lines
37 - 50, The generated helper method Get{{.Name}} is hard-coded to the receiver
type *ICoreWebView2; change the template so the receiver is the actual base
interface type instead of ICoreWebView2 (use the template's base-class symbol,
e.g. {{.BaseClass}} or the correct field that holds the base interface name) so
the generated signature becomes func (i *<actualBase>) Get{{.Name}}(), and
ensure the rest of the body still uses iid{{.Name}},
NewGUID({{.Header.AsString}}) and i.Vtbl.QueryInterface.Call as before.


{{end}}
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