Support multi-variable selects and typed selects

This adds support for selecting on multiple variables at once, so that
you can do AND/OR combindations of them. For example:

select((
    arch(),
    os(),
), {
    ("arm64", "linux"): ["libfoo64"],
    (default, "linux"): ["libfoo"],
    (default, "windows"): ["libfoowindows"],
    (default, default): ["libbar"],
})

It also allows for select conditions to be boolean-typed. You can
write literal true and false without quotes to select on them. Currently
we don't have any boolean-typed variables though, so a fake one was
added for testing.

Bug: 323382414
Test: m nothing --no-skip-soong-tests
Change-Id: Ibe586e7b21865b8734027848cc421594cbd1d8cc

9 files changed, 842 insertions, 316 deletions

diff --git a/parser/ast.go b/parser/ast.go
index 68f15ed..7aea5e0 100644
--- a/parser/ast.go
+++ b/parser/ast.go
@@ -571,37 +571,46 @@ func endPos(pos scanner.Position, n int) scanner.Position {
 	return pos
 }
 
-type SelectType int
-
-const (
-	SelectTypeUnconfigured SelectType = iota // Used for selects with only one branch, which is "default"
-	SelectTypeReleaseVariable
-	SelectTypeSoongConfigVariable
-	SelectTypeProductVariable
-	SelectTypeVariant
-)
+type ConfigurableCondition struct {
+	position     scanner.Position
+	FunctionName string
+	Args         []String
+}
 
-func (s SelectType) String() string {
-	switch s {
-	case SelectTypeUnconfigured:
-		return "unconfigured"
-	case SelectTypeReleaseVariable:
-		return "release variable"
-	case SelectTypeSoongConfigVariable:
-		return "soong config variable"
-	case SelectTypeProductVariable:
-		return "product variable"
-	case SelectTypeVariant:
-		return "variant"
-	default:
-		panic("unreachable")
+func (c *ConfigurableCondition) Equals(other ConfigurableCondition) bool {
+	if c.FunctionName != other.FunctionName {
+		return false
+	}
+	if len(c.Args) != len(other.Args) {
+		return false
+	}
+	for i := range c.Args {
+		if c.Args[i] != other.Args[i] {
+			return false
+		}
+	}
+	return true
+}
+
+func (c *ConfigurableCondition) String() string {
+	var sb strings.Builder
+	sb.WriteString(c.FunctionName)
+	sb.WriteRune('(')
+	for i, arg := range c.Args {
+		sb.WriteRune('"')
+		sb.WriteString(arg.Value)
+		sb.WriteRune('"')
+		if i < len(c.Args)-1 {
+			sb.WriteString(", ")
+		}
 	}
+	sb.WriteRune(')')
+	return sb.String()
 }
 
 type Select struct {
 	KeywordPos     scanner.Position // the keyword "select"
-	Typ            SelectType
-	Condition      String
+	Conditions     []ConfigurableCondition
 	LBracePos      scanner.Position
 	RBracePos      scanner.Position
 	Cases          []*SelectCase // the case statements
@@ -640,8 +649,7 @@ func (s *Select) Type() Type {
 }
 
 type SelectCase struct {
-	// TODO: Support int and bool typed cases
-	Pattern  String
+	Patterns []Expression
 	ColonPos scanner.Position
 	Value    Expression
 }
@@ -656,7 +664,7 @@ func (c *SelectCase) String() string {
 	return "<select case>"
 }
 
-func (c *SelectCase) Pos() scanner.Position { return c.Pattern.LiteralPos }
+func (c *SelectCase) Pos() scanner.Position { return c.Patterns[0].Pos() }
 func (c *SelectCase) End() scanner.Position { return c.Value.End() }
 
 // UnsetProperty is the expression type of the "unset" keyword that can be
diff --git a/parser/parser.go b/parser/parser.go
index 07f4681..eaed054 100644
--- a/parser/parser.go
+++ b/parser/parser.go
@@ -28,6 +28,8 @@ var errTooManyErrors = errors.New("too many errors")
 
 const maxErrors = 1
 
+const default_select_branch_name = "__soong_conditions_default__"
+
 type ParseError struct {
 	Err error
 	Pos scanner.Position
@@ -177,7 +179,6 @@ func (p *parser) next() {
 			p.comments = append(p.comments, &CommentGroup{Comments: comments})
 		}
 	}
-	return
 }
 
 func (p *parser) parseDefinitions() (defs []Definition) {
@@ -386,11 +387,7 @@ func (p *parser) evaluateOperator(value1, value2 Expression, operator rune,
 			if _, ok := e2.(*Select); ok {
 				// Promote e1 to a select so we can add e2 to it
 				e1 = &Select{
-					Typ: SelectTypeUnconfigured,
 					Cases: []*SelectCase{{
-						Pattern: String{
-							Value: "__soong_conditions_default__",
-						},
 						Value: e1,
 					}},
 				}
@@ -563,49 +560,81 @@ func (p *parser) parseSelect() Expression {
 	result := &Select{
 		KeywordPos: p.scanner.Position,
 	}
-	p.accept(scanner.Ident)
-	if !p.accept('(') {
-		return nil
-	}
-	switch p.scanner.TokenText() {
-	case "release_variable":
-		result.Typ = SelectTypeReleaseVariable
-	case "soong_config_variable":
-		result.Typ = SelectTypeSoongConfigVariable
-	case "product_variable":
-		result.Typ = SelectTypeProductVariable
-	case "variant":
-		result.Typ = SelectTypeVariant
-	default:
-		p.errorf("unknown select type %q, expected release_variable, soong_config_variable, product_variable, or variant", p.scanner.TokenText())
-		return nil
-	}
+	// Read the "select("
 	p.accept(scanner.Ident)
 	if !p.accept('(') {
 		return nil
 	}
 
-	if s := p.parseStringValue(); s != nil {
-		result.Condition = *s
-	} else {
-		return nil
+	// If we see another '(', there's probably multiple conditions and there must
+	// be a ')' after. Set the multipleConditions variable to remind us to check for
+	// the ')' after.
+	multipleConditions := false
+	if p.tok == '(' {
+		multipleConditions = true
+		p.accept('(')
 	}
 
-	if result.Typ == SelectTypeSoongConfigVariable {
-		if !p.accept(',') {
+	// Read all individual conditions
+	conditions := []ConfigurableCondition{}
+	for first := true; first || multipleConditions; first = false {
+		condition := ConfigurableCondition{
+			position:     p.scanner.Position,
+			FunctionName: p.scanner.TokenText(),
+		}
+		if !p.accept(scanner.Ident) {
 			return nil
 		}
-		if s := p.parseStringValue(); s != nil {
-			result.Condition.Value += ":" + s.Value
-		} else {
+		if !p.accept('(') {
 			return nil
 		}
+
+		for p.tok != ')' {
+			if s := p.parseStringValue(); s != nil {
+				condition.Args = append(condition.Args, *s)
+			} else {
+				return nil
+			}
+			if p.tok == ')' {
+				break
+			}
+			if !p.accept(',') {
+				return nil
+			}
+		}
+		p.accept(')')
+
+		for _, c := range conditions {
+			if c.Equals(condition) {
+				p.errorf("Duplicate select condition found: %s", c.String())
+			}
+		}
+
+		conditions = append(conditions, condition)
+
+		if multipleConditions {
+			if p.tok == ')' {
+				p.next()
+				break
+			}
+			if !p.accept(',') {
+				return nil
+			}
+			// Retry the closing parent to allow for a trailing comma
+			if p.tok == ')' {
+				p.next()
+				break
+			}
+		}
 	}
 
-	if !p.accept(')') {
+	if multipleConditions && len(conditions) < 2 {
+		p.errorf("Expected multiple select conditions due to the extra parenthesis, but only found 1. Please remove the extra parenthesis.")
 		return nil
 	}
 
+	result.Conditions = conditions
+
 	if !p.accept(',') {
 		return nil
 	}
@@ -615,17 +644,78 @@ func (p *parser) parseSelect() Expression {
 		return nil
 	}
 
+	parseOnePattern := func() Expression {
+		switch p.tok {
+		case scanner.Ident:
+			switch p.scanner.TokenText() {
+			case "default":
+				p.next()
+				return &String{
+					LiteralPos: p.scanner.Position,
+					Value:      default_select_branch_name,
+				}
+			case "true":
+				p.next()
+				return &Bool{
+					LiteralPos: p.scanner.Position,
+					Value:      true,
+				}
+			case "false":
+				p.next()
+				return &Bool{
+					LiteralPos: p.scanner.Position,
+					Value:      false,
+				}
+			default:
+				p.errorf("Expted a string, true, false, or default, got %s", p.scanner.TokenText())
+			}
+		case scanner.String:
+			if s := p.parseStringValue(); s != nil {
+				if strings.HasPrefix(s.Value, "__soong") {
+					p.errorf("select branch conditions starting with __soong are reserved for internal use")
+					return nil
+				}
+				return s
+			}
+			fallthrough
+		default:
+			p.errorf("Expted a string, true, false, or default, got %s", p.scanner.TokenText())
+		}
+		return nil
+	}
+
 	hasNonUnsetValue := false
-	for p.tok == scanner.String {
+	for p.tok != '}' {
 		c := &SelectCase{}
-		if s := p.parseStringValue(); s != nil {
-			if strings.HasPrefix(s.Value, "__soong") {
-				p.errorf("select branch conditions starting with __soong are reserved for internal use")
+
+		if multipleConditions {
+			if !p.accept('(') {
+				return nil
+			}
+			for i := 0; i < len(conditions); i++ {
+				if p := parseOnePattern(); p != nil {
+					c.Patterns = append(c.Patterns, p)
+				} else {
+					return nil
+				}
+				if i < len(conditions)-1 {
+					if !p.accept(',') {
+						return nil
+					}
+				} else if p.tok == ',' {
+					// allow optional trailing comma
+					p.next()
+				}
+			}
+			if !p.accept(')') {
 				return nil
 			}
-			c.Pattern = *s
 		} else {
-			return nil
+			if p := parseOnePattern(); p != nil {
+				c.Patterns = append(c.Patterns, p)
+			} else {
+				return nil
+			}
 		}
 		c.ColonPos = p.scanner.Position
 		if !p.accept(':') {
@@ -641,44 +731,70 @@ func (p *parser) parseSelect() Expression {
 		if !p.accept(',') {
 			return nil
 		}
-
 		result.Cases = append(result.Cases, c)
 	}
 
-	// Default must be last
-	if p.tok == scanner.Ident {
-		if p.scanner.TokenText() != "default" {
-			p.errorf("select cases can either be quoted strings or 'default' to match any value")
-			return nil
-		}
-		c := &SelectCase{Pattern: String{
-			LiteralPos: p.scanner.Position,
-			Value:      "__soong_conditions_default__",
-		}}
-		p.accept(scanner.Ident)
-		c.ColonPos = p.scanner.Position
-		if !p.accept(':') {
-			return nil
+	// If all branches have the value "unset", then this is equivalent
+	// to an empty select.
+	if !hasNonUnsetValue {
+		p.errorf("This select statement is empty, remove it")
+		return nil
+	}
+
+	patternsEqual := func(a, b Expression) bool {
+		switch a2 := a.(type) {
+		case *String:
+			if b2, ok := b.(*String); ok {
+				return a2.Value == b2.Value
+			} else {
+				return false
+			}
+		case *Bool:
+			if b2, ok := b.(*Bool); ok {
+				return a2.Value == b2.Value
+			} else {
+				return false
+			}
+		default:
+			// true so that we produce an error in this unexpected scenario
+			return true
 		}
-		if p.tok == scanner.Ident && p.scanner.TokenText() == "unset" {
-			c.Value = UnsetProperty{Position: p.scanner.Position}
-			p.accept(scanner.Ident)
-		} else {
-			hasNonUnsetValue = true
-			c.Value = p.parseExpression()
+	}
+
+	patternListsEqual := func(a, b []Expression) bool {
+		if len(a) != len(b) {
+			return false
 		}
-		if !p.accept(',') {
-			return nil
+		for i := range a {
+			if !patternsEqual(a[i], b[i]) {
+				return false
+			}
 		}
-		result.Cases = append(result.Cases, c)
+		return true
 	}
 
-	// If all branches have the value "unset", then this is equivalent
-	// to an empty select.
-	if !hasNonUnsetValue {
-		result.Typ = SelectTypeUnconfigured
-		result.Condition.Value = ""
-		result.Cases = nil
+	for i, c := range result.Cases {
+		// Check for duplicates
+		for _, d := range result.Cases[i+1:] {
+			if patternListsEqual(c.Patterns, d.Patterns) {
+				p.errorf("Found duplicate select patterns: %v", c.Patterns)
+				return nil
+			}
+		}
+		// Check that the only all-default cases is the last one
+		if i < len(result.Cases)-1 {
+			isAllDefault := true
+			for _, x := range c.Patterns {
+				if x2, ok := x.(*String); !ok || x2.Value != default_select_branch_name {
+					isAllDefault = false
+					break
+				}
+			}
+			if isAllDefault {
+				p.errorf("Found a default select branch at index %d, expected it to be last (index %d)", i, len(result.Cases)-1)
+				return nil
+			}
+		}
 	}
 
 	ty := UnsetType
diff --git a/parser/parser_test.go b/parser/parser_test.go
index b393792..9de69c0 100644
--- a/parser/parser_test.go
+++ b/parser/parser_test.go
@@ -1225,6 +1225,17 @@ func TestParserError(t *testing.T) {
 			input: "\x00",
 			err:   "invalid character NUL",
 		},
+		{
+			name: "select with duplicate condition",
+			input: `
+			m {
+				foo: select((arch(), arch()), {
+					(default, default): true,
+				}),
+			}
+			`,
+			err: "Duplicate select condition found: arch()",
+		},
 		// TODO: test more parser errors
 	}
 
diff --git a/parser/printer.go b/parser/printer.go
index 9d83e7a..848b95a 100644
--- a/parser/printer.go
+++ b/parser/printer.go
@@ -142,48 +142,83 @@ func (p *printer) printSelect(s *Select) {
 	if len(s.Cases) == 0 {
 		return
 	}
-	if len(s.Cases) == 1 && s.Cases[0].Pattern.Value == "__soong_conditions_default__" {
-		p.printExpression(s.Cases[0].Value)
-		p.pos = s.RBracePos
-		return
+	if len(s.Cases) == 1 && len(s.Cases[0].Patterns) == 1 {
+		if str, ok := s.Cases[0].Patterns[0].(*String); ok && str.Value == default_select_branch_name {
+			p.printExpression(s.Cases[0].Value)
+			p.pos = s.RBracePos
+			return
+		}
 	}
 	p.requestSpace()
 	p.printToken("select(", s.KeywordPos)
-	switch s.Typ {
-	case SelectTypeSoongConfigVariable:
-		p.printToken("soong_config_variable(", s.Condition.LiteralPos)
-		parts := strings.Split(s.Condition.Value, ":")
-		namespace := parts[0]
-		variable := parts[1]
-		p.printToken(strconv.Quote(namespace), s.Condition.LiteralPos)
-		p.printToken(",", s.Condition.LiteralPos)
-		p.requestSpace()
-		p.printToken(strconv.Quote(variable), s.Condition.LiteralPos)
-		p.printToken(")", s.Condition.LiteralPos)
-	case SelectTypeReleaseVariable:
-		p.printToken("release_variable(", s.Condition.LiteralPos)
-		p.printToken(strconv.Quote(s.Condition.Value), s.Condition.LiteralPos)
-		p.printToken(")", s.Condition.LiteralPos)
-	case SelectTypeProductVariable:
-		p.printToken("product_variable(", s.Condition.LiteralPos)
-		p.printToken(strconv.Quote(s.Condition.Value), s.Condition.LiteralPos)
-		p.printToken(")", s.Condition.LiteralPos)
-	case SelectTypeVariant:
-		p.printToken("variant(", s.Condition.LiteralPos)
-		p.printToken(strconv.Quote(s.Condition.Value), s.Condition.LiteralPos)
-		p.printToken(")", s.Condition.LiteralPos)
-	default:
-		panic("should be unreachable")
+	multilineConditions := false
+	if len(s.Conditions) > 1 {
+		p.printToken("(", s.KeywordPos)
+		if s.Conditions[len(s.Conditions)-1].position.Line > s.KeywordPos.Line {
+			multilineConditions = true
+			p.requestNewline()
+			p.indent(p.curIndent() + 4)
+		}
+	}
+	for i, c := range s.Conditions {
+		p.printToken(c.FunctionName, c.position)
+		p.printToken("(", c.position)
+		for i, arg := range c.Args {
+			p.printToken(strconv.Quote(arg.Value), arg.LiteralPos)
+			if i < len(c.Args)-1 {
+				p.printToken(",", arg.LiteralPos)
+				p.requestSpace()
+			}
+		}
+		p.printToken(")", p.pos)
+		if len(s.Conditions) > 1 {
+			if multilineConditions {
+				p.printToken(",", p.pos)
+				p.requestNewline()
+			} else if i < len(s.Conditions)-1 {
+				p.printToken(",", p.pos)
+				p.requestSpace()
+			}
+		}
+	}
+	if len(s.Conditions) > 1 {
+		if multilineConditions {
+			p.unindent(p.pos)
+		}
+		p.printToken(")", p.pos)
 	}
 	p.printToken(", {", s.LBracePos)
 	p.requestNewline()
 	p.indent(p.curIndent() + 4)
 	for _, c := range s.Cases {
 		p.requestNewline()
-		if c.Pattern.Value != "__soong_conditions_default__" {
-			p.printToken(strconv.Quote(c.Pattern.Value), c.Pattern.LiteralPos)
-		} else {
-			p.printToken("default", c.Pattern.LiteralPos)
+		if len(c.Patterns) > 1 {
+			p.printToken("(", p.pos)
+		}
+		for i, pat := range c.Patterns {
+			switch pat := pat.(type) {
+			case *String:
+				if pat.Value != default_select_branch_name {
+					p.printToken(strconv.Quote(pat.Value), pat.LiteralPos)
+				} else {
+					p.printToken("default", pat.LiteralPos)
+				}
+			case *Bool:
+				s := "false"
+				if pat.Value {
+					s = "true"
+				}
+				p.printToken(s, pat.LiteralPos)
+			default:
+				panic("Unhandled case")
+			}
+			if i < len(c.Patterns)-1 {
+				p.printToken(",", p.pos)
+				p.requestSpace()
+			}
+		}
+		if len(c.Patterns) > 1 {
+			p.printToken(")", p.pos)
 		}
 		p.printToken(":", c.ColonPos)
 		p.requestSpace()
diff --git a/parser/printer_test.go b/parser/printer_test.go
index e273115..3a81551 100644
--- a/parser/printer_test.go
+++ b/parser/printer_test.go
@@ -657,50 +657,44 @@ foo {
 `,
 	},
 	{
-		name: "Select with only unsets is removed",
+		name: "Multi-condition select",
 		input: `
 foo {
-    stuff: select(soong_config_variable("my_namespace", "my_variable"), {
-        "foo": unset,
-        default: unset,
+    stuff: select((arch(), os()), {
+        ("x86", "linux"): "a",
+        (default, default): "b",
     }),
 }
 `,
 		output: `
 foo {
-
+    stuff: select((arch(), os()), {
+        ("x86", "linux"): "a",
+        (default, default): "b",
+    }),
 }
 `,
 	},
 	{
-		name: "Additions of unset selects are removed",
+		name: "Multi-condition select with conditions on new lines",
 		input: `
 foo {
-    stuff: select(soong_config_variable("my_namespace", "my_variable"), {
-        "foo": "a",
-        default: "b",
-    }) + select(soong_config_variable("my_namespace", "my_variable2"), {
-        "foo": unset,
-        default: unset,
-    }) + select(soong_config_variable("my_namespace", "my_variable3"), {
-        "foo": "c",
-        default: "d",
+    stuff: select((arch(), 
+    os()), {
+        ("x86", "linux"): "a",
+        (default, default): "b",
     }),
 }
 `,
-		// TODO(b/323382414): This is not good formatting, revisit later.
-		// But at least it removes the useless middle select
 		output: `
 foo {
-    stuff: select(soong_config_variable("my_namespace", "my_variable"), {
-        "foo": "a",
-        default: "b",
-    }) +
-
-        select(soong_config_variable("my_namespace", "my_variable3"), {
-            "foo": "c",
-            default: "d",
-        }),
+    stuff: select((
+        arch(),
+        os(),
+    ), {
+        ("x86", "linux"): "a",
+        (default, default): "b",
+    }),
 }
 `,
 	},
diff --git a/proptools/configurable.go b/proptools/configurable.go
index 6d88fae..b136f59 100644
--- a/proptools/configurable.go
+++ b/proptools/configurable.go
@@ -14,21 +14,18 @@
 package proptools
 
 import (
-	"fmt"
 	"reflect"
 	"slices"
-
-	"github.com/google/blueprint/parser"
+	"strconv"
+	"strings"
 )
 
-const default_select_branch_name = "__soong_conditions_default__"
-
 type ConfigurableElements interface {
 	string | bool | []string
 }
 
 type ConfigurableEvaluator interface {
-	EvaluateConfiguration(typ parser.SelectType, property, condition string) (string, bool)
+	EvaluateConfiguration(condition ConfigurableCondition, property string) ConfigurableValue
 	PropertyErrorf(property, fmt string, args ...interface{})
 }
 
@@ -38,6 +35,200 @@ type configurableMarker bool
 
 var configurableMarkerType reflect.Type = reflect.TypeOf((*configurableMarker)(nil)).Elem()
 
+type ConfigurableCondition struct {
+	FunctionName string
+	Args         []string
+}
+
+func (c *ConfigurableCondition) String() string {
+	var sb strings.Builder
+	sb.WriteString(c.FunctionName)
+	sb.WriteRune('(')
+	for i, arg := range c.Args {
+		sb.WriteString(strconv.Quote(arg))
+		if i < len(c.Args)-1 {
+			sb.WriteString(", ")
+		}
+	}
+	sb.WriteRune(')')
+	return sb.String()
+}
+
+type configurableValueType int
+
+const (
+	configurableValueTypeString configurableValueType = iota
+	configurableValueTypeBool
+	configurableValueTypeUndefined
+)
+
+func (v *configurableValueType) patternType() configurablePatternType {
+	switch *v {
+	case configurableValueTypeString:
+		return configurablePatternTypeString
+	case configurableValueTypeBool:
+		return configurablePatternTypeBool
+	default:
+		panic("unimplemented")
+	}
+}
+
+func (v *configurableValueType) String() string {
+	switch *v {
+	case configurableValueTypeString:
+		return "string"
+	case configurableValueTypeBool:
+		return "bool"
+	case configurableValueTypeUndefined:
+		return "undefined"
+	default:
+		panic("unimplemented")
+	}
+}
+
+// ConfigurableValue represents the value of a certain condition being selected on.
+// This type mostly exists to act as a sum type between string, bool, and undefined.
+type ConfigurableValue struct {
+	typ         configurableValueType
+	stringValue string
+	boolValue   bool
+}
+
+func (c *ConfigurableValue) String() string {
+	switch c.typ {
+	case configurableValueTypeString:
+		return strconv.Quote(c.stringValue)
+	case configurableValueTypeBool:
+		if c.boolValue {
+			return "true"
+		} else {
+			return "false"
+		}
+	case configurableValueTypeUndefined:
+		return "undefined"
+	default:
+		panic("unimplemented")
+	}
+}
+
+func ConfigurableValueString(s string) ConfigurableValue {
+	return ConfigurableValue{
+		typ:         configurableValueTypeString,
+		stringValue: s,
+	}
+}
+
+func ConfigurableValueBool(b bool) ConfigurableValue {
+	return ConfigurableValue{
+		typ:       configurableValueTypeBool,
+		boolValue: b,
+	}
+}
+
+func ConfigurableValueUndefined() ConfigurableValue {
+	return ConfigurableValue{
+		typ: configurableValueTypeUndefined,
+	}
+}
+
+type configurablePatternType int
+
+const (
+	configurablePatternTypeString configurablePatternType = iota
+	configurablePatternTypeBool
+	configurablePatternTypeDefault
+)
+
+func (v *configurablePatternType) String() string {
+	switch *v {
+	case configurablePatternTypeString:
+		return "string"
+	case configurablePatternTypeBool:
+		return "bool"
+	case configurablePatternTypeDefault:
+		return "default"
+	default:
+		panic("unimplemented")
+	}
+}
+
+type configurablePattern struct {
+	typ         configurablePatternType
+	stringValue string
+	boolValue   bool
+}
+
+func (p *configurablePattern) matchesValue(v ConfigurableValue) bool {
+	if p.typ == configurablePatternTypeDefault {
+		return true
+	}
+	if v.typ == configurableValueTypeUndefined {
+		return false
+	}
+	if p.typ != v.typ.patternType() {
+		return false
+	}
+	switch p.typ {
+	case configurablePatternTypeString:
+		return p.stringValue == v.stringValue
+	case configurablePatternTypeBool:
+		return p.boolValue == v.boolValue
+	default:
+		panic("unimplemented")
+	}
+}
+
+func (p *configurablePattern) matchesValueType(v ConfigurableValue) bool {
+	if p.typ == configurablePatternTypeDefault {
+		return true
+	}
+	if v.typ == configurableValueTypeUndefined {
+		return true
+	}
+	return p.typ == v.typ.patternType()
+}
+
+type configurableCase[T ConfigurableElements] struct {
+	patterns []configurablePattern
+	value    *T
+}
+
+func (c *configurableCase[T]) Clone() configurableCase[T] {
+	return configurableCase[T]{
+		patterns: slices.Clone(c.patterns),
+		value:    copyConfiguredValue(c.value),
+	}
+}
+
+type configurableCaseReflection interface {
+	initialize(patterns []configurablePattern, value interface{})
+}
+
+var _ configurableCaseReflection = &configurableCase[string]{}
+
+func (c *configurableCase[T]) initialize(patterns []configurablePattern, value interface{}) {
+	c.patterns = patterns
+	c.value = value.(*T)
+}
+
+// for the given T, return the reflect.type of configurableCase[T]
+func configurableCaseType(configuredType reflect.Type) reflect.Type {
+	// I don't think it's possible to do this generically with go's
+	// current reflection apis unfortunately
+	switch configuredType.Kind() {
+	case reflect.String:
+		return reflect.TypeOf(configurableCase[string]{})
+	case reflect.Bool:
+		return reflect.TypeOf(configurableCase[bool]{})
+	case reflect.Slice:
+		switch configuredType.Elem().Kind() {
+		case reflect.String:
+			return reflect.TypeOf(configurableCase[[]string]{})
+		}
+	}
+	panic("unimplemented")
+}
+
 // Configurable can wrap the type of a blueprint property,
 // in order to allow select statements to be used in bp files
 // for that property. For example, for the property struct:
@@ -51,11 +242,11 @@ var configurableMarkerType reflect.Type = reflect.TypeOf((*configurableMarker)(n
 //
 //	my_module {
 //	  property_a: "foo"
-//	  property_b: select soong_config_variable: "my_namespace" "my_variable" {
+//	  property_b: select(soong_config_variable("my_namespace", "my_variable"), {
 //	    "value_1": "bar",
 //	    "value_2": "baz",
 //	    default: "qux",
-//	  }
+//	  })
 //	}
 //
 // The configurable property holds all the branches of the select
@@ -67,9 +258,8 @@ var configurableMarkerType reflect.Type = reflect.TypeOf((*configurableMarker)(n
 type Configurable[T ConfigurableElements] struct {
 	marker        configurableMarker
 	propertyName  string
-	typ           parser.SelectType
-	condition     string
-	cases         map[string]*T
+	conditions    []ConfigurableCondition
+	cases         []configurableCase[T]
 	appendWrapper *appendWrapper[T]
 }
 
@@ -112,40 +302,49 @@ func (c *Configurable[T]) GetOrDefault(evaluator ConfigurableEvaluator, defaultV
 }
 
 func (c *Configurable[T]) evaluateNonTransitive(evaluator ConfigurableEvaluator) *T {
-	if c.typ == parser.SelectTypeUnconfigured {
-		if len(c.cases) == 0 {
+	for i, case_ := range c.cases {
+		if len(c.conditions) != len(case_.patterns) {
+			evaluator.PropertyErrorf(c.propertyName, "Expected each case to have as many patterns as conditions. conditions: %d, len(cases[%d].patterns): %d", len(c.conditions), i, len(case_.patterns))
 			return nil
-		} else if len(c.cases) != 1 {
-			panic(fmt.Sprintf("Expected 0 or 1 branches in an unconfigured select, found %d", len(c.cases)))
 		}
-		result, ok := c.cases[default_select_branch_name]
-		if !ok {
-			actual := ""
-			for k := range c.cases {
-				actual = k
-			}
-			panic(fmt.Sprintf("Expected the single branch of an unconfigured select to be %q, got %q", default_select_branch_name, actual))
-		}
-		return result
 	}
-	val, defined := evaluator.EvaluateConfiguration(c.typ, c.propertyName, c.condition)
-	if !defined {
-		if result, ok := c.cases[default_select_branch_name]; ok {
-			return result
+	if len(c.conditions) == 0 {
+		if len(c.cases) == 0 {
+			return nil
+		} else if len(c.cases) == 1 {
+			return c.cases[0].value
+		} else {
+			evaluator.PropertyErrorf(c.propertyName, "Expected 0 or 1 branches in an unconfigured select, found %d", len(c.cases))
+			return nil
 		}
-		evaluator.PropertyErrorf(c.propertyName, "%s %q was not defined", c.typ.String(), c.condition)
-		return nil
 	}
-	if val == default_select_branch_name {
-		panic("Evaluator cannot return the default branch")
+	values := make([]ConfigurableValue, len(c.conditions))
+	for i, condition := range c.conditions {
+		values[i] = evaluator.EvaluateConfiguration(condition, c.propertyName)
 	}
-	if result, ok := c.cases[val]; ok {
-		return result
+	foundMatch := false
+	var result *T
+	for _, case_ := range c.cases {
+		allMatch := true
+		for i, pat := range case_.patterns {
+			if !pat.matchesValueType(values[i]) {
+				evaluator.PropertyErrorf(c.propertyName, "Expected all branches of a select on condition %s to have type %s, found %s", c.conditions[i].String(), values[i].typ.String(), pat.typ.String())
+				return nil
+			}
+			if !pat.matchesValue(values[i]) {
+				allMatch = false
+				break
+			}
+		}
+		if allMatch && !foundMatch {
+			result = case_.value
+			foundMatch = true
+		}
 	}
-	if result, ok := c.cases[default_select_branch_name]; ok {
+	if foundMatch {
 		return result
 	}
-	evaluator.PropertyErrorf(c.propertyName, "%s %q had value %q, which was not handled by the select statement", c.typ.String(), c.condition, val)
+	evaluator.PropertyErrorf(c.propertyName, "%s had value %s, which was not handled by the select statement", c.conditions, values)
 	return nil
 }
 
@@ -216,17 +415,16 @@ type configurableReflection interface {
 // Same as configurableReflection, but since initialize needs to take a pointer
 // to a Configurable, it was broken out into a separate interface.
 type configurablePtrReflection interface {
-	initialize(propertyName string, typ parser.SelectType, condition string, cases any)
+	initialize(propertyName string, conditions []ConfigurableCondition, cases any)
 }
 
 var _ configurableReflection = Configurable[string]{}
 var _ configurablePtrReflection = &Configurable[string]{}
 
-func (c *Configurable[T]) initialize(propertyName string, typ parser.SelectType, condition string, cases any) {
+func (c *Configurable[T]) initialize(propertyName string, conditions []ConfigurableCondition, cases any) {
 	c.propertyName = propertyName
-	c.typ = typ
-	c.condition = condition
-	c.cases = cases.(map[string]*T)
+	c.conditions = conditions
+	c.cases = cases.([]configurableCase[T])
 	c.appendWrapper = &appendWrapper[T]{}
 }
 
@@ -243,7 +441,7 @@ func (c Configurable[T]) isEmpty() bool {
 	if c.appendWrapper != nil && !c.appendWrapper.append.isEmpty() {
 		return false
 	}
-	return c.typ == parser.SelectTypeUnconfigured && len(c.cases) == 0
+	return len(c.cases) == 0
 }
 
 func (c Configurable[T]) configuredType() reflect.Type {
@@ -267,15 +465,17 @@ func (c *Configurable[T]) clone() *Configurable[T] {
 		}
 	}
 
-	casesCopy := make(map[string]*T, len(c.cases))
-	for k, v := range c.cases {
-		casesCopy[k] = copyConfiguredValue(v)
+	conditionsCopy := make([]ConfigurableCondition, len(c.conditions))
+	copy(conditionsCopy, c.conditions)
+
+	casesCopy := make([]configurableCase[T], len(c.cases))
+	for i, case_ := range c.cases {
+		casesCopy[i] = case_.Clone()
 	}
 
 	return &Configurable[T]{
 		propertyName:  c.propertyName,
-		typ:           c.typ,
-		condition:     c.condition,
+		conditions:    conditionsCopy,
 		cases:         casesCopy,
 		appendWrapper: inner,
 	}
diff --git a/proptools/extend_test.go b/proptools/extend_test.go
index 498ce29..9b07c78 100644
--- a/proptools/extend_test.go
+++ b/proptools/extend_test.go
@@ -20,8 +20,6 @@ import (
 	"reflect"
 	"strings"
 	"testing"
-
-	"github.com/google/blueprint/parser"
 )
 
 type appendPropertyTestCase struct {
@@ -1260,38 +1258,72 @@ func appendPropertiesTestCases() []appendPropertyTestCase {
 			name: "Append configurable",
 			dst: &struct{ S Configurable[[]string] }{
 				S: Configurable[[]string]{
-					typ:       parser.SelectTypeSoongConfigVariable,
-					condition: "foo",
-					cases: map[string]*[]string{
-						"a": {"1", "2"},
-					},
+					conditions: []ConfigurableCondition{{
+						FunctionName: "soong_config_variable",
+						Args: []string{
+							"my_namespace",
+							"foo",
+						},
+					}},
+					cases: []configurableCase[[]string]{{
+						patterns: []configurablePattern{{
+							typ:         configurablePatternTypeString,
+							stringValue: "a",
+						}},
+						value: &[]string{"1", "2"},
+					}},
 					appendWrapper: &appendWrapper[[]string]{},
 				},
 			},
 			src: &struct{ S Configurable[[]string] }{
 				S: Configurable[[]string]{
-					typ:       parser.SelectTypeReleaseVariable,
-					condition: "bar",
-					cases: map[string]*[]string{
-						"b": {"3", "4"},
-					},
+					conditions: []ConfigurableCondition{{
+						FunctionName: "release_variable",
+						Args: []string{
+							"bar",
+						},
+					}},
+					cases: []configurableCase[[]string]{{
+						patterns: []configurablePattern{{
+							typ:         configurablePatternTypeString,
+							stringValue: "b",
+						}},
+						value: &[]string{"3", "4"},
+					}},
 					appendWrapper: &appendWrapper[[]string]{},
 				},
 			},
 			out: &struct{ S Configurable[[]string] }{
 				S: Configurable[[]string]{
-					typ:       parser.SelectTypeSoongConfigVariable,
-					condition: "foo",
-					cases: map[string]*[]string{
-						"a": {"1", "2"},
-					},
+					conditions: []ConfigurableCondition{{
+						FunctionName: "soong_config_variable",
+						Args: []string{
+							"my_namespace",
+							"foo",
+						},
+					}},
+					cases: []configurableCase[[]string]{{
+						patterns: []configurablePattern{{
+							typ:         configurablePatternTypeString,
+							stringValue: "a",
+						}},
+						value: &[]string{"1", "2"},
+					}},
 					appendWrapper: &appendWrapper[[]string]{
 						append: Configurable[[]string]{
-							typ:       parser.SelectTypeReleaseVariable,
-							condition: "bar",
-							cases: map[string]*[]string{
-								"b": {"3", "4"},
-							},
+							conditions: []ConfigurableCondition{{
+								FunctionName: "release_variable",
+								Args: []string{
+									"bar",
+								},
+							}},
+							cases: []configurableCase[[]string]{{
+								patterns: []configurablePattern{{
+									typ:         configurablePatternTypeString,
+									stringValue: "b",
+								}},
+								value: &[]string{"3", "4"},
+							}},
 							appendWrapper: &appendWrapper[[]string]{},
 						},
 					},
@@ -1303,38 +1335,72 @@ func appendPropertiesTestCases() []appendPropertyTestCase {
 			order: Prepend,
 			dst: &struct{ S Configurable[[]string] }{
 				S: Configurable[[]string]{
-					typ:       parser.SelectTypeSoongConfigVariable,
-					condition: "foo",
-					cases: map[string]*[]string{
-						"a": {"1", "2"},
-					},
+					conditions: []ConfigurableCondition{{
+						FunctionName: "soong_config_variable",
+						Args: []string{
+							"my_namespace",
+							"foo",
+						},
+					}},
+					cases: []configurableCase[[]string]{{
+						patterns: []configurablePattern{{
+							typ:         configurablePatternTypeString,
+							stringValue: "a",
+						}},
+						value: &[]string{"1", "2"},
+					}},
 					appendWrapper: &appendWrapper[[]string]{},
 				},
 			},
 			src: &struct{ S Configurable[[]string] }{
 				S: Configurable[[]string]{
-					typ:       parser.SelectTypeReleaseVariable,
-					condition: "bar",
-					cases: map[string]*[]string{
-						"b": {"3", "4"},
-					},
+					conditions: []ConfigurableCondition{{
+						FunctionName: "release_variable",
+						Args: []string{
+							"bar",
+						},
+					}},
+					cases: []configurableCase[[]string]{{
+						patterns: []configurablePattern{{
+							typ:         configurablePatternTypeString,
+							stringValue: "b",
+						}},
+						value: &[]string{"3", "4"},
+					}},
 					appendWrapper: &appendWrapper[[]string]{},
 				},
 			},
 			out: &struct{ S Configurable[[]string] }{
 				S: Configurable[[]string]{
-					typ:       parser.SelectTypeReleaseVariable,
-					condition: "bar",
-					cases: map[string]*[]string{
-						"b": {"3", "4"},
-					},
+					conditions: []ConfigurableCondition{{
+						FunctionName: "release_variable",
+						Args: []string{
+							"bar",
+						},
+					}},
+					cases: []configurableCase[[]string]{{
+						patterns: []configurablePattern{{
+							typ:         configurablePatternTypeString,
+							stringValue: "b",
+						}},
+						value: &[]string{"3", "4"},
+					}},
 					appendWrapper: &appendWrapper[[]string]{
 						append: Configurable[[]string]{
-							typ:       parser.SelectTypeSoongConfigVariable,
-							condition: "foo",
-							cases: map[string]*[]string{
-								"a": {"1", "2"},
-							},
+							conditions: []ConfigurableCondition{{
+								FunctionName: "soong_config_variable",
+								Args: []string{
+									"my_namespace",
+									"foo",
+								},
+							}},
+							cases: []configurableCase[[]string]{{
+								patterns: []configurablePattern{{
+									typ:         configurablePatternTypeString,
+									stringValue: "a",
+								}},
+								value: &[]string{"1", "2"},
+							}},
 							appendWrapper: &appendWrapper[[]string]{},
 						},
 					},
diff --git a/proptools/unpack.go b/proptools/unpack.go
index 85709cc..53b2b2f 100644
--- a/proptools/unpack.go
+++ b/proptools/unpack.go
@@ -356,10 +356,9 @@ func (ctx *unpackContext) unpackToConfigurable(propertyName string, property *pa
 		}
 		result := Configurable[string]{
 			propertyName: property.Name,
-			typ:          parser.SelectTypeUnconfigured,
-			cases: map[string]*string{
-				default_select_branch_name: &v.Value,
-			},
+			cases: []configurableCase[string]{{
+				value: &v.Value,
+			}},
 			appendWrapper: &appendWrapper[string]{},
 		}
 		return reflect.ValueOf(&result), true
@@ -374,10 +373,9 @@ func (ctx *unpackContext) unpackToConfigurable(propertyName string, property *pa
 		}
 		result := Configurable[bool]{
 			propertyName: property.Name,
-			typ:          parser.SelectTypeUnconfigured,
-			cases: map[string]*bool{
-				default_select_branch_name: &v.Value,
-			},
+			cases: []configurableCase[bool]{{
+				value: &v.Value,
+			}},
 			appendWrapper: &appendWrapper[bool]{},
 		}
 		return reflect.ValueOf(&result), true
@@ -392,9 +390,9 @@ func (ctx *unpackContext) unpackToConfigurable(propertyName string, property *pa
 		}
 		switch configuredType.Elem().Kind() {
 		case reflect.String:
-			var cases map[string]*[]string
+			var value []string
 			if v.Values != nil {
-				value := make([]string, 0, len(v.Values))
+				value = make([]string, len(v.Values))
 				itemProperty := &parser.Property{NamePos: property.NamePos, ColonPos: property.ColonPos}
 				for i, expr := range v.Values {
 					itemProperty.Name = propertyName + "[" + strconv.Itoa(i) + "]"
@@ -404,14 +402,14 @@ func (ctx *unpackContext) unpackToConfigurable(propertyName string, property *pa
 						ctx.addError(err)
 						return reflect.ValueOf(Configurable[[]string]{}), false
 					}
-					value = append(value, exprUnpacked.Interface().(string))
+					value[i] = exprUnpacked.Interface().(string)
 				}
-				cases = map[string]*[]string{default_select_branch_name: &value}
 			}
 			result := Configurable[[]string]{
-				propertyName:  property.Name,
-				typ:           parser.SelectTypeUnconfigured,
-				cases:         cases,
+				propertyName: property.Name,
+				cases: []configurableCase[[]string]{{
+					value: &value,
+				}},
 				appendWrapper: &appendWrapper[[]string]{},
 			}
 			return reflect.ValueOf(&result), true
@@ -424,46 +422,81 @@ func (ctx *unpackContext) unpackToConfigurable(propertyName string, property *pa
 	case *parser.Select:
 		resultPtr := reflect.New(configurableType)
 		result := resultPtr.Elem()
-		cases := reflect.MakeMapWithSize(reflect.MapOf(reflect.TypeOf(""), reflect.PointerTo(configuredType)), len(v.Cases))
+		conditions := make([]ConfigurableCondition, len(v.Conditions))
+		for i, cond := range v.Conditions {
+			args := make([]string, len(cond.Args))
+			for j, arg := range cond.Args {
+				args[j] = arg.Value
+			}
+			conditions[i] = ConfigurableCondition{
+				FunctionName: cond.FunctionName,
+				Args:         args,
+			}
+		}
+
+		configurableCaseType := configurableCaseType(configuredType)
+		cases := reflect.MakeSlice(reflect.SliceOf(configurableCaseType), 0, len(v.Cases))
 		for i, c := range v.Cases {
 			p := &parser.Property{
 				Name:    property.Name + "[" + strconv.Itoa(i) + "]",
 				NamePos: c.ColonPos,
 				Value:   c.Value,
 			}
+
+			patterns := make([]configurablePattern, len(c.Patterns))
+			for i, pat := range c.Patterns {
+				switch pat := pat.(type) {
+				case *parser.String:
+					if pat.Value == "__soong_conditions_default__" {
+						patterns[i].typ = configurablePatternTypeDefault
+					} else {
+						patterns[i].typ = configurablePatternTypeString
+						patterns[i].stringValue = pat.Value
+					}
+				case *parser.Bool:
+					patterns[i].typ = configurablePatternTypeBool
+					patterns[i].boolValue = pat.Value
+				default:
+					panic("unimplemented")
+				}
+			}
+
+			var value reflect.Value
 			// Map the "unset" keyword to a nil pointer in the cases map
 			if _, ok := c.Value.(parser.UnsetProperty); ok {
-				cases.SetMapIndex(reflect.ValueOf(c.Pattern.Value), reflect.Zero(reflect.PointerTo(configuredType)))
-				continue
-			}
-			switch configuredType.Kind() {
-			case reflect.String, reflect.Bool:
-				val, err := propertyToValue(reflect.PointerTo(configuredType), p)
-				if err != nil {
-					ctx.addError(&UnpackError{
-						err,
-						c.Value.Pos(),
-					})
-					return reflect.New(configurableType), false
-				}
-				cases.SetMapIndex(reflect.ValueOf(c.Pattern.Value), val)
-			case reflect.Slice:
-				if configuredType.Elem().Kind() != reflect.String {
-					panic("This should be unreachable because ConfigurableElements only accepts slices of strings")
-				}
-				val, ok := ctx.unpackToSlice(p.Name, p, reflect.PointerTo(configuredType))
-				if !ok {
-					return reflect.New(configurableType), false
+				value = reflect.Zero(reflect.PointerTo(configuredType))
+			} else {
+				var err error
+				switch configuredType.Kind() {
+				case reflect.String, reflect.Bool:
+					value, err = propertyToValue(reflect.PointerTo(configuredType), p)
+					if err != nil {
+						ctx.addError(&UnpackError{
+							err,
+							c.Value.Pos(),
+						})
+						return reflect.New(configurableType), false
+					}
+				case reflect.Slice:
+					if configuredType.Elem().Kind() != reflect.String {
+						panic("This should be unreachable because ConfigurableElements only accepts slices of strings")
+					}
+					value, ok = ctx.unpackToSlice(p.Name, p, reflect.PointerTo(configuredType))
+					if !ok {
+						return reflect.New(configurableType), false
+					}
+				default:
+					panic("This should be unreachable because ConfigurableElements only accepts strings, boools, or slices of strings")
 				}
-				cases.SetMapIndex(reflect.ValueOf(c.Pattern.Value), val)
-			default:
-				panic("This should be unreachable because ConfigurableElements only accepts strings, boools, or slices of strings")
 			}
+
+			case_ := reflect.New(configurableCaseType)
+			case_.Interface().(configurableCaseReflection).initialize(patterns, value.Interface())
+			cases = reflect.Append(cases, case_.Elem())
 		}
 		resultPtr.Interface().(configurablePtrReflection).initialize(
 			property.Name,
-			v.Typ,
-			v.Condition.Value,
+			conditions,
 			cases.Interface(),
 		)
 		if v.Append != nil {
diff --git a/proptools/unpack_test.go b/proptools/unpack_test.go
index 7b7b46b..3182c8b 100644
--- a/proptools/unpack_test.go
+++ b/proptools/unpack_test.go
@@ -734,10 +734,9 @@ var validUnpackTestCases = []struct {
 			}{
 				Foo: Configurable[string]{
 					propertyName: "foo",
-					typ:          parser.SelectTypeUnconfigured,
-					cases: map[string]*string{
-						default_select_branch_name: StringPtr("bar"),
-					},
+					cases: []configurableCase[string]{{
+						value: StringPtr("bar"),
+					}},
 					appendWrapper: &appendWrapper[string]{},
 				},
 			},
@@ -756,10 +755,9 @@ var validUnpackTestCases = []struct {
 			}{
 				Foo: Configurable[bool]{
 					propertyName: "foo",
-					typ:          parser.SelectTypeUnconfigured,
-					cases: map[string]*bool{
-						default_select_branch_name: BoolPtr(true),
-					},
+					cases: []configurableCase[bool]{{
+						value: BoolPtr(true),
+					}},
 					appendWrapper: &appendWrapper[bool]{},
 				},
 			},
@@ -778,10 +776,9 @@ var validUnpackTestCases = []struct {
 			}{
 				Foo: Configurable[[]string]{
 					propertyName: "foo",
-					typ:          parser.SelectTypeUnconfigured,
-					cases: map[string]*[]string{
-						default_select_branch_name: {"a", "b"},
-					},
+					cases: []configurableCase[[]string]{{
+						value: &[]string{"a", "b"},
+					}},
 					appendWrapper: &appendWrapper[[]string]{},
 				},
 			},
@@ -804,12 +801,34 @@ var validUnpackTestCases = []struct {
 			}{
 				Foo: Configurable[string]{
 					propertyName: "foo",
-					typ:          parser.SelectTypeSoongConfigVariable,
-					condition:    "my_namespace:my_variable",
-					cases: map[string]*string{
-						"a":                        StringPtr("a2"),
-						"b":                        StringPtr("b2"),
-						default_select_branch_name: StringPtr("c2"),
+					conditions: []ConfigurableCondition{{
+						FunctionName: "soong_config_variable",
+						Args: []string{
+							"my_namespace",
+							"my_variable",
+						},
+					}},
+					cases: []configurableCase[string]{
+						{
+							patterns: []configurablePattern{{
+								typ:         configurablePatternTypeString,
+								stringValue: "a",
+							}},
+							value: StringPtr("a2"),
+						},
+						{
+							patterns: []configurablePattern{{
+								typ:         configurablePatternTypeString,
+								stringValue: "b",
+							}},
+							value: StringPtr("b2"),
+						},
+						{
+							patterns: []configurablePattern{{
+								typ: configurablePatternTypeDefault,
+							}},
+							value: StringPtr("c2"),
+						},
 					},
 					appendWrapper: &appendWrapper[string]{},
 				},
@@ -837,22 +856,66 @@ var validUnpackTestCases = []struct {
 			}{
 				Foo: Configurable[string]{
 					propertyName: "foo",
-					typ:          parser.SelectTypeSoongConfigVariable,
-					condition:    "my_namespace:my_variable",
-					cases: map[string]*string{
-						"a":                        StringPtr("a2"),
-						"b":                        StringPtr("b2"),
-						default_select_branch_name: StringPtr("c2"),
+					conditions: []ConfigurableCondition{{
+						FunctionName: "soong_config_variable",
+						Args: []string{
+							"my_namespace",
+							"my_variable",
+						},
+					}},
+					cases: []configurableCase[string]{
+						{
+							patterns: []configurablePattern{{
+								typ:         configurablePatternTypeString,
+								stringValue: "a",
+							}},
+							value: StringPtr("a2"),
+						},
+						{
+							patterns: []configurablePattern{{
+								typ:         configurablePatternTypeString,
+								stringValue: "b",
+							}},
+							value: StringPtr("b2"),
+						},
+						{
+							patterns: []configurablePattern{{
+								typ: configurablePatternTypeDefault,
+							}},
+							value: StringPtr("c2"),
+						},
 					},
 					appendWrapper: &appendWrapper[string]{
 						append: Configurable[string]{
 							propertyName: "foo",
-							typ:          parser.SelectTypeSoongConfigVariable,
-							condition:    "my_namespace:my_2nd_variable",
-							cases: map[string]*string{
-								"d":                        StringPtr("d2"),
-								"e":                        StringPtr("e2"),
-								default_select_branch_name: StringPtr("f2"),
+							conditions: []ConfigurableCondition{{
+								FunctionName: "soong_config_variable",
+								Args: []string{
+									"my_namespace",
+									"my_2nd_variable",
+								},
+							}},
+							cases: []configurableCase[string]{
+								{
+									patterns: []configurablePattern{{
+										typ:         configurablePatternTypeString,
+										stringValue: "d",
+									}},
+									value: StringPtr("d2"),
+								},
+								{
+									patterns: []configurablePattern{{
+										typ:         configurablePatternTypeString,
+										stringValue: "e",
+									}},
+									value: StringPtr("e2"),
+								},
+								{
+									patterns: []configurablePattern{{
+										typ: configurablePatternTypeDefault,
+									}},
+									value: StringPtr("f2"),
+								},
 							},
 							appendWrapper: &appendWrapper[string]{},
 						},