(#46) fix: change BuildInformation to an interface

CHANGELOG.md

@@ -15,9 +15,17 @@ Key to symbols
 - 😒 change is invisible to the user
 - 🆕 new feature
 
+## v0.24.1
+
+_release `2024.10.28`_
+
+- 🐛⚠️ change `BuildInformation` from a `struct` to an `interface` for easier mocking by consumers. Consequently,
+`GetBuildInfo` returns an _implementation_ of `BuildInformation` instead of a pointer to an instance of
+`BuildInformation`.
+
 ## v0.24.0
 
-_release `2024.10.27`_
+_release `2024.10.28`_
 
 - 🆕add `GetBuildData(reader func() (*debug.BuildInfo, bool)) *BuildInformation`; this also adds the `BuildInformation`
 struct and four methods on `*BuildInformation`:

about.go

@@ -9,37 +9,44 @@ import (
 	"github.com/majohn-r/output"
 )
 
-// BuildInformation holds data about the build
-type BuildInformation struct {
+// BuildInformation provides data about the build
+type BuildInformation interface {
+	GoVersion() string
+	Dependencies() []string
+	MainVersion() string
+	Settings() []string
+}
+
+type buildInformation struct {
 	goVersion    string
 	dependencies []string
 	mainVersion  string
 	settings     []string
 }
 
 // GoVersion returns the version of Go used to build the code
-func (bi *BuildInformation) GoVersion() string {
+func (bi *buildInformation) GoVersion() string {
 	return bi.goVersion
 }
 
 // Dependencies returns an alphabetically sorted slice of dependency data (path and version for each dependency)
-func (bi *BuildInformation) Dependencies() []string {
+func (bi *buildInformation) Dependencies() []string {
 	return bi.dependencies
 }
 
 // MainVersion returns the git version of the main module
-func (bi *BuildInformation) MainVersion() string {
+func (bi *buildInformation) MainVersion() string {
 	return bi.mainVersion
 }
 
 // Settings returns an alphabetically sorted slice of build settings used to build the code
-func (bi *BuildInformation) Settings() []string {
+func (bi *buildInformation) Settings() []string {
 	return bi.settings
 }
 
 // GetBuildData returns the build data, if any, obtained from the provided reader function
-func GetBuildData(reader func() (*debug.BuildInfo, bool)) *BuildInformation {
-	bi := &BuildInformation{
+func GetBuildData(reader func() (*debug.BuildInfo, bool)) BuildInformation {
+	bi := &buildInformation{
 		goVersion:    "unknown",
 		dependencies: []string{},
 		mainVersion:  "unknown",
@@ -76,8 +83,8 @@ func GetBuildData(reader func() (*debug.BuildInfo, bool)) *BuildInformation {
 // callers, pass in debug.ReadBuildInfo
 func InterpretBuildData(buildInfoReader func() (*debug.BuildInfo, bool)) (goVersion string, dependencies []string) {
 	bi := GetBuildData(buildInfoReader)
-	goVersion = bi.goVersion
-	dependencies = bi.dependencies
+	goVersion = bi.GoVersion()
+	dependencies = bi.Dependencies()
 	return
 }