Export ConfigurableCase and add constructors

Some soong code sets arch-variant properties in order to control a
module's default behavior. I'll make this continue to work, but long
term the arch-variant properties should be replaced with selects,
so expose an API for creating select statements in soong code.

Bug: 323382414
Test: m nothing --no-skip-soong-tests
Change-Id: I6c65d6e112b6f826f1027777b6fdf36915d34b1d

4 files changed, 94 insertions, 53 deletions

diff --git a/proptools/configurable.go b/proptools/configurable.go
index b136f59..f521ab4 100644
--- a/proptools/configurable.go
+++ b/proptools/configurable.go
@@ -14,6 +14,7 @@
 package proptools
 
 import (
+	"fmt"
 	"reflect"
 	"slices"
 	"strconv"
@@ -152,13 +153,33 @@ func (v *configurablePatternType) String() string {
 	}
 }
 
-type configurablePattern struct {
+type ConfigurablePattern struct {
 	typ         configurablePatternType
 	stringValue string
 	boolValue   bool
 }
 
-func (p *configurablePattern) matchesValue(v ConfigurableValue) bool {
+func NewStringConfigurablePattern(s string) ConfigurablePattern {
+	return ConfigurablePattern{
+		typ:         configurablePatternTypeString,
+		stringValue: s,
+	}
+}
+
+func NewBoolConfigurablePattern(b bool) ConfigurablePattern {
+	return ConfigurablePattern{
+		typ:       configurablePatternTypeBool,
+		boolValue: b,
+	}
+}
+
+func NewDefaultConfigurablePattern() ConfigurablePattern {
+	return ConfigurablePattern{
+		typ: configurablePatternTypeDefault,
+	}
+}
+
+func (p *ConfigurablePattern) matchesValue(v ConfigurableValue) bool {
 	if p.typ == configurablePatternTypeDefault {
 		return true
 	}
@@ -178,7 +199,7 @@ func (p *configurablePattern) matchesValue(v ConfigurableValue) bool {
 	}
 }
 
-func (p *configurablePattern) matchesValueType(v ConfigurableValue) bool {
+func (p *ConfigurablePattern) matchesValueType(v ConfigurableValue) bool {
 	if p.typ == configurablePatternTypeDefault {
 		return true
 	}
@@ -188,25 +209,32 @@ func (p *configurablePattern) matchesValueType(v ConfigurableValue) bool {
 	return p.typ == v.typ.patternType()
 }
 
-type configurableCase[T ConfigurableElements] struct {
-	patterns []configurablePattern
+type ConfigurableCase[T ConfigurableElements] struct {
+	patterns []ConfigurablePattern
 	value    *T
 }
 
-func (c *configurableCase[T]) Clone() configurableCase[T] {
-	return configurableCase[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{})
+	initialize(patterns []ConfigurablePattern, value interface{})
 }
 
-var _ configurableCaseReflection = &configurableCase[string]{}
+var _ configurableCaseReflection = &ConfigurableCase[string]{}
 
-func (c *configurableCase[T]) initialize(patterns []configurablePattern, value interface{}) {
+func NewConfigurableCase[T ConfigurableElements](patterns []ConfigurablePattern, value *T) ConfigurableCase[T] {
+	return ConfigurableCase[T]{
+		patterns: patterns,
+		value:    value,
+	}
+}
+
+func (c *ConfigurableCase[T]) initialize(patterns []ConfigurablePattern, value interface{}) {
 	c.patterns = patterns
 	c.value = value.(*T)
 }
@@ -217,13 +245,13 @@ func configurableCaseType(configuredType reflect.Type) reflect.Type {
 	// current reflection apis unfortunately
 	switch configuredType.Kind() {
 	case reflect.String:
-		return reflect.TypeOf(configurableCase[string]{})
+		return reflect.TypeOf(ConfigurableCase[string]{})
 	case reflect.Bool:
-		return reflect.TypeOf(configurableCase[bool]{})
+		return reflect.TypeOf(ConfigurableCase[bool]{})
 	case reflect.Slice:
 		switch configuredType.Elem().Kind() {
 		case reflect.String:
-			return reflect.TypeOf(configurableCase[[]string]{})
+			return reflect.TypeOf(ConfigurableCase[[]string]{})
 		}
 	}
 	panic("unimplemented")
@@ -259,13 +287,26 @@ type Configurable[T ConfigurableElements] struct {
 	marker        configurableMarker
 	propertyName  string
 	conditions    []ConfigurableCondition
-	cases         []configurableCase[T]
+	cases         []ConfigurableCase[T]
 	appendWrapper *appendWrapper[T]
 }
 
 // Ignore the warning about the unused marker variable, it's used via reflection
 var _ configurableMarker = Configurable[string]{}.marker
 
+func NewConfigurable[T ConfigurableElements](conditions []ConfigurableCondition, cases []ConfigurableCase[T]) Configurable[T] {
+	for _, c := range cases {
+		if len(c.patterns) != len(conditions) {
+			panic(fmt.Sprintf("All configurables cases must have as many patterns as the configurable has conditions. Expected: %d, found: %d", len(conditions), len(c.patterns)))
+		}
+	}
+	return Configurable[T]{
+		conditions:    conditions,
+		cases:         cases,
+		appendWrapper: &appendWrapper[T]{},
+	}
+}
+
 // appendWrapper exists so that we can set the value of append
 // from a non-pointer method receiver. (setAppend)
 type appendWrapper[T ConfigurableElements] struct {
@@ -424,7 +465,7 @@ var _ configurablePtrReflection = &Configurable[string]{}
 func (c *Configurable[T]) initialize(propertyName string, conditions []ConfigurableCondition, cases any) {
 	c.propertyName = propertyName
 	c.conditions = conditions
-	c.cases = cases.([]configurableCase[T])
+	c.cases = cases.([]ConfigurableCase[T])
 	c.appendWrapper = &appendWrapper[T]{}
 }
 
@@ -468,7 +509,7 @@ func (c *Configurable[T]) clone() *Configurable[T] {
 	conditionsCopy := make([]ConfigurableCondition, len(c.conditions))
 	copy(conditionsCopy, c.conditions)
 
-	casesCopy := make([]configurableCase[T], len(c.cases))
+	casesCopy := make([]ConfigurableCase[T], len(c.cases))
 	for i, case_ := range c.cases {
 		casesCopy[i] = case_.Clone()
 	}
diff --git a/proptools/extend_test.go b/proptools/extend_test.go
index 9b07c78..b2920f5 100644
--- a/proptools/extend_test.go
+++ b/proptools/extend_test.go
@@ -1265,8 +1265,8 @@ func appendPropertiesTestCases() []appendPropertyTestCase {
 							"foo",
 						},
 					}},
-					cases: []configurableCase[[]string]{{
-						patterns: []configurablePattern{{
+					cases: []ConfigurableCase[[]string]{{
+						patterns: []ConfigurablePattern{{
 							typ:         configurablePatternTypeString,
 							stringValue: "a",
 						}},
@@ -1283,8 +1283,8 @@ func appendPropertiesTestCases() []appendPropertyTestCase {
 							"bar",
 						},
 					}},
-					cases: []configurableCase[[]string]{{
-						patterns: []configurablePattern{{
+					cases: []ConfigurableCase[[]string]{{
+						patterns: []ConfigurablePattern{{
 							typ:         configurablePatternTypeString,
 							stringValue: "b",
 						}},
@@ -1302,8 +1302,8 @@ func appendPropertiesTestCases() []appendPropertyTestCase {
 							"foo",
 						},
 					}},
-					cases: []configurableCase[[]string]{{
-						patterns: []configurablePattern{{
+					cases: []ConfigurableCase[[]string]{{
+						patterns: []ConfigurablePattern{{
 							typ:         configurablePatternTypeString,
 							stringValue: "a",
 						}},
@@ -1317,8 +1317,8 @@ func appendPropertiesTestCases() []appendPropertyTestCase {
 									"bar",
 								},
 							}},
-							cases: []configurableCase[[]string]{{
-								patterns: []configurablePattern{{
+							cases: []ConfigurableCase[[]string]{{
+								patterns: []ConfigurablePattern{{
 									typ:         configurablePatternTypeString,
 									stringValue: "b",
 								}},
@@ -1342,8 +1342,8 @@ func appendPropertiesTestCases() []appendPropertyTestCase {
 							"foo",
 						},
 					}},
-					cases: []configurableCase[[]string]{{
-						patterns: []configurablePattern{{
+					cases: []ConfigurableCase[[]string]{{
+						patterns: []ConfigurablePattern{{
 							typ:         configurablePatternTypeString,
 							stringValue: "a",
 						}},
@@ -1360,8 +1360,8 @@ func appendPropertiesTestCases() []appendPropertyTestCase {
 							"bar",
 						},
 					}},
-					cases: []configurableCase[[]string]{{
-						patterns: []configurablePattern{{
+					cases: []ConfigurableCase[[]string]{{
+						patterns: []ConfigurablePattern{{
 							typ:         configurablePatternTypeString,
 							stringValue: "b",
 						}},
@@ -1378,8 +1378,8 @@ func appendPropertiesTestCases() []appendPropertyTestCase {
 							"bar",
 						},
 					}},
-					cases: []configurableCase[[]string]{{
-						patterns: []configurablePattern{{
+					cases: []ConfigurableCase[[]string]{{
+						patterns: []ConfigurablePattern{{
 							typ:         configurablePatternTypeString,
 							stringValue: "b",
 						}},
@@ -1394,8 +1394,8 @@ func appendPropertiesTestCases() []appendPropertyTestCase {
 									"foo",
 								},
 							}},
-							cases: []configurableCase[[]string]{{
-								patterns: []configurablePattern{{
+							cases: []ConfigurableCase[[]string]{{
+								patterns: []ConfigurablePattern{{
 									typ:         configurablePatternTypeString,
 									stringValue: "a",
 								}},
diff --git a/proptools/unpack.go b/proptools/unpack.go
index 5886cb1..0cddcdb 100644
--- a/proptools/unpack.go
+++ b/proptools/unpack.go
@@ -356,7 +356,7 @@ func (ctx *unpackContext) unpackToConfigurable(propertyName string, property *pa
 		}
 		result := Configurable[string]{
 			propertyName: property.Name,
-			cases: []configurableCase[string]{{
+			cases: []ConfigurableCase[string]{{
 				value: &v.Value,
 			}},
 			appendWrapper: &appendWrapper[string]{},
@@ -373,7 +373,7 @@ func (ctx *unpackContext) unpackToConfigurable(propertyName string, property *pa
 		}
 		result := Configurable[bool]{
 			propertyName: property.Name,
-			cases: []configurableCase[bool]{{
+			cases: []ConfigurableCase[bool]{{
 				value: &v.Value,
 			}},
 			appendWrapper: &appendWrapper[bool]{},
@@ -407,7 +407,7 @@ func (ctx *unpackContext) unpackToConfigurable(propertyName string, property *pa
 			}
 			result := Configurable[[]string]{
 				propertyName: property.Name,
-				cases: []configurableCase[[]string]{{
+				cases: []ConfigurableCase[[]string]{{
 					value: &value,
 				}},
 				appendWrapper: &appendWrapper[[]string]{},
@@ -446,7 +446,7 @@ func (ctx *unpackContext) unpackToConfigurable(propertyName string, property *pa
 				Value:   c.Value,
 			}
 
-			patterns := make([]configurablePattern, len(c.Patterns))
+			patterns := make([]ConfigurablePattern, len(c.Patterns))
 			for i, pat := range c.Patterns {
 				switch pat := pat.(type) {
 				case *parser.String:
diff --git a/proptools/unpack_test.go b/proptools/unpack_test.go
index fee7c9c..009c65b 100644
--- a/proptools/unpack_test.go
+++ b/proptools/unpack_test.go
@@ -734,7 +734,7 @@ var validUnpackTestCases = []struct {
 			}{
 				Foo: Configurable[string]{
 					propertyName: "foo",
-					cases: []configurableCase[string]{{
+					cases: []ConfigurableCase[string]{{
 						value: StringPtr("bar"),
 					}},
 					appendWrapper: &appendWrapper[string]{},
@@ -755,7 +755,7 @@ var validUnpackTestCases = []struct {
 			}{
 				Foo: Configurable[bool]{
 					propertyName: "foo",
-					cases: []configurableCase[bool]{{
+					cases: []ConfigurableCase[bool]{{
 						value: BoolPtr(true),
 					}},
 					appendWrapper: &appendWrapper[bool]{},
@@ -776,7 +776,7 @@ var validUnpackTestCases = []struct {
 			}{
 				Foo: Configurable[[]string]{
 					propertyName: "foo",
-					cases: []configurableCase[[]string]{{
+					cases: []ConfigurableCase[[]string]{{
 						value: &[]string{"a", "b"},
 					}},
 					appendWrapper: &appendWrapper[[]string]{},
@@ -808,23 +808,23 @@ var validUnpackTestCases = []struct {
 							"my_variable",
 						},
 					}},
-					cases: []configurableCase[string]{
+					cases: []ConfigurableCase[string]{
 						{
-							patterns: []configurablePattern{{
+							patterns: []ConfigurablePattern{{
 								typ:         configurablePatternTypeString,
 								stringValue: "a",
 							}},
 							value: StringPtr("a2"),
 						},
 						{
-							patterns: []configurablePattern{{
+							patterns: []ConfigurablePattern{{
 								typ:         configurablePatternTypeString,
 								stringValue: "b",
 							}},
 							value: StringPtr("b2"),
 						},
 						{
-							patterns: []configurablePattern{{
+							patterns: []ConfigurablePattern{{
 								typ: configurablePatternTypeDefault,
 							}},
 							value: StringPtr("c2"),
@@ -863,23 +863,23 @@ var validUnpackTestCases = []struct {
 							"my_variable",
 						},
 					}},
-					cases: []configurableCase[string]{
+					cases: []ConfigurableCase[string]{
 						{
-							patterns: []configurablePattern{{
+							patterns: []ConfigurablePattern{{
 								typ:         configurablePatternTypeString,
 								stringValue: "a",
 							}},
 							value: StringPtr("a2"),
 						},
 						{
-							patterns: []configurablePattern{{
+							patterns: []ConfigurablePattern{{
 								typ:         configurablePatternTypeString,
 								stringValue: "b",
 							}},
 							value: StringPtr("b2"),
 						},
 						{
-							patterns: []configurablePattern{{
+							patterns: []ConfigurablePattern{{
 								typ: configurablePatternTypeDefault,
 							}},
 							value: StringPtr("c2"),
@@ -895,23 +895,23 @@ var validUnpackTestCases = []struct {
 									"my_2nd_variable",
 								},
 							}},
-							cases: []configurableCase[string]{
+							cases: []ConfigurableCase[string]{
 								{
-									patterns: []configurablePattern{{
+									patterns: []ConfigurablePattern{{
 										typ:         configurablePatternTypeString,
 										stringValue: "d",
 									}},
 									value: StringPtr("d2"),
 								},
 								{
-									patterns: []configurablePattern{{
+									patterns: []ConfigurablePattern{{
 										typ:         configurablePatternTypeString,
 										stringValue: "e",
 									}},
 									value: StringPtr("e2"),
 								},
 								{
-									patterns: []configurablePattern{{
+									patterns: []ConfigurablePattern{{
 										typ: configurablePatternTypeDefault,
 									}},
 									value: StringPtr("f2"),
@@ -941,7 +941,7 @@ var validUnpackTestCases = []struct {
 			}{
 				Foo: Configurable[string]{
 					propertyName: "foo",
-					cases: []configurableCase[string]{
+					cases: []ConfigurableCase[string]{
 						{
 							value: StringPtr("asdf"),
 						},
@@ -950,7 +950,7 @@ var validUnpackTestCases = []struct {
 				},
 				Bar: Configurable[bool]{
 					propertyName: "bar",
-					cases: []configurableCase[bool]{
+					cases: []ConfigurableCase[bool]{
 						{
 							value: BoolPtr(true),
 						},