ebiten: panic if a non-existent uniform variable name is given

Closes #2710

image.go

@@ -581,6 +581,8 @@ var _ [len(DrawTrianglesShaderOptions{}.Images) - graphics.ShaderImageCount]stru
 //
 // If a specified uniform variable's length or type doesn't match with an expected one, DrawTrianglesShader panics.
 //
+// If a non-existent uniform variable name is specified, DrawTrianglesShader panics.
+//
 // When the image i is disposed, DrawTrianglesShader does nothing.
 func (i *Image) DrawTrianglesShader(vertices []Vertex, indices []uint16, shader *Shader, options *DrawTrianglesShaderOptions) {
 	i.copyCheck()
@@ -732,6 +734,8 @@ var _ [len(DrawRectShaderOptions{}.Images)]struct{} = [graphics.ShaderImageCount
 //
 // If a specified uniform variable's length or type doesn't match with an expected one, DrawRectShader panics.
 //
+// If a non-existent uniform variable name is specified, DrawRectShader panics.
+//
 // When the image i is disposed, DrawRectShader does nothing.
 func (i *Image) DrawRectShader(width, height int, shader *Shader, options *DrawRectShaderOptions) {
 	i.copyCheck()

internal/ui/shader.go

@@ -46,6 +46,22 @@ func (s *Shader) MarkDisposed() {
 }
 
 func (s *Shader) AppendUniforms(dst []uint32, uniforms map[string]any) []uint32 {
+	// Check the given names are valid.
+	// This is a linear search and not efficient, but the number of uniform variables should not be so big.
+	for n := range uniforms {
+		var found bool
+		for _, nn := range s.uniformNames {
+			if n == nn {
+				found = true
+				break
+			}
+		}
+		if found {
+			continue
+		}
+		panic(fmt.Sprintf("ui: unexpected uniform name: %s", n))
+	}
+
 	if s.uniformUint32Count == 0 {
 		for _, typ := range s.uniformTypes {
 			s.uniformUint32Count += typ.Uint32Count()
@@ -67,7 +83,6 @@ func (s *Shader) AppendUniforms(dst []uint32, uniforms map[string]any) []uint32
 		typ := s.uniformTypes[i]
 
 		if uv, ok := uniforms[name]; ok {
-			// TODO: Panic if uniforms include an invalid name
 			v := reflect.ValueOf(uv)
 			t := v.Type()
 			switch t.Kind() {

shader_test.go

@@ -1942,6 +1942,18 @@ func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
 			},
 			err: true,
 		},
+		{
+			uniforms: map[string]any{
+				"W": 1,
+			},
+			err: true,
+		},
+		{
+			uniforms: map[string]any{
+				"W": []int32{1, 2, 3},
+			},
+			err: true,
+		},
 	}
 	for _, tc := range tests {
 		tc := tc