Change remove subcommand behaviour to show error when breaking installed package dependencies

src/bpm/main.go

@@ -92,7 +92,6 @@ func main() {
 		currentFlagSet.BoolP("verbose", "v", false, "Show additional information about the current operation")
 		currentFlagSet.BoolP("force", "f", false, "Bypass warnings during package removal")
 		currentFlagSet.BoolP("yes", "y", false, "Enter 'yes' in all prompts")
-		currentFlagSet.BoolP("unused", "u", false, "Remove packages only if they are not required as dependencies")
 		currentFlagSet.BoolP("cleanup", "n", false, "Additionally remove all unused dependencies")
 		setupFlagsAndHelp(currentFlagSet, fmt.Sprintf("bpm %s <options>", subcommand), "Remove the specified packages", os.Args[2:])
 
@@ -496,7 +495,6 @@ func removePackages() {
 	verbose, _ := currentFlagSet.GetBool("verbose")
 	force, _ := currentFlagSet.GetBool("force")
 	yesAll, _ := currentFlagSet.GetBool("yes")
-	removeUnused, _ := currentFlagSet.GetBool("unused")
 	cleanupPackages, _ := currentFlagSet.GetBool("cleanup")
 
 	// Get packages
@@ -527,8 +525,16 @@ func removePackages() {
 	}
 
 	// Create remove operation
-	operation, err := bpmlib.RemovePackages(rootDir, removeUnused, cleanupPackages, packages...)
+	operation, err := bpmlib.RemovePackages(rootDir, force, cleanupPackages, packages...)
 	if errors.As(err, &bpmlib.PackageNotFoundErr{}) || errors.As(err, &bpmlib.DependencyNotFoundErr{}) || errors.As(err, &bpmlib.PackageConflictErr{}) {
+		log.Printf("Error: %s", err)
+		exitCode = 1
+		return
+	} else if errors.As(err, &bpmlib.PackageRemovalDependencyErr{}) {
+		for pkg, dependants := range err.(bpmlib.PackageRemovalDependencyErr).RequiredPackages {
+			fmt.Printf("The following packages depend on package (%s): %s\n", pkg, strings.Join(dependants, ", "))
+		}
+
 		log.Printf("Error: %s", err)
 		exitCode = 1
 		return

src/bpmlib/dependencies.go

@@ -198,12 +198,9 @@ func GetPackageDependants(pkgName string, rootDir string) ([]string, error) {
 			continue
 		}
 
-		// Get installed package dependencies
-		dependencies := installedPkg.PkgInfo.GetDependencies(false, true)
-
 		// Add installed package to list if its dependencies include pkgName
-		if slices.ContainsFunc(dependencies, func(p pkgInstallationReason) bool {
-			return p.PkgName == pkgName
+		if slices.ContainsFunc(installedPkg.PkgInfo.Depends, func(n string) bool {
+			return n == pkgName
 		}) {
 			ret = append(ret, installedPkgName)
 			continue
@@ -212,8 +209,8 @@ func GetPackageDependants(pkgName string, rootDir string) ([]string, error) {
 		// Loop through each virtual package
 		for _, vpkg := range pkg.PkgInfo.Provides {
 			// Add installed package to list if its dependencies contain a provided virtual package
-			if slices.ContainsFunc(dependencies, func(p pkgInstallationReason) bool {
-				return p.PkgName == vpkg
+			if slices.ContainsFunc(installedPkg.PkgInfo.Depends, func(n string) bool {
+				return n == vpkg
 			}) {
 				ret = append(ret, installedPkgName)
 				break

src/bpmlib/errors.go

@@ -40,3 +40,11 @@ type PackageScriptErr struct {
 func (e PackageScriptErr) Error() string {
 	return fmt.Sprintf("could not execute package script (%s) for package (%s): %s", e.packageScript, e.packageName, e.err)
 }
+
+type PackageRemovalDependencyErr struct {
+	RequiredPackages map[string][]string
+}
+
+func (e PackageRemovalDependencyErr) Error() string {
+	return "removing these package would break other installed packages"
+}

src/bpmlib/general.go

@@ -4,6 +4,7 @@ import (
 	"errors"
 	"fmt"
 	"log"
+	"maps"
 	"os"
 	"path"
 	"slices"
@@ -186,7 +187,7 @@ func InstallPackages(rootDir string, forceInstallationReason InstallationReason,
 }
 
 // RemovePackages removes the specified packages from the given root directory
-func RemovePackages(rootDir string, removeUnusedPackagesOnly, cleanupDependencies bool, packages ...string) (operation *BPMOperation, err error) {
+func RemovePackages(rootDir string, force, cleanupDependencies bool, packages ...string) (operation *BPMOperation, err error) {
 	operation = &BPMOperation{
 		Actions:           make([]OperationAction, 0),
 		UnresolvedDepends: make([]string, 0),
@@ -204,14 +205,6 @@ func RemovePackages(rootDir string, removeUnusedPackagesOnly, cleanupDependencie
 		operation.AppendAction(&RemovePackageAction{BpmPackage: bpmpkg})
 	}
 
-	// Do not remove packages which other packages depend on
-	if removeUnusedPackagesOnly {
-		err := operation.RemoveNeededPackages()
-		if err != nil {
-			return nil, fmt.Errorf("could not skip needed packages: %s", err)
-		}
-	}
-
 	// Do package cleanup
 	if cleanupDependencies {
 		err := operation.Cleanup(true)
@@ -219,6 +212,40 @@ func RemovePackages(rootDir string, removeUnusedPackagesOnly, cleanupDependencie
 			return nil, fmt.Errorf("could not perform cleanup for operation: %s", err)
 		}
 	}
+
+	// Return error if other packages depend on removed ones
+	if !force {
+		// Get packages and their dependants
+		packageDepndants := make(map[string][]string, 0)
+		for _, action := range operation.Actions {
+			dependants, err := GetPackageDependants(action.(*RemovePackageAction).BpmPackage.PkgInfo.Name, rootDir)
+			if err != nil {
+				return nil, fmt.Errorf("could not get package dependants: %s", err)
+			}
+
+			packageDepndants[action.(*RemovePackageAction).BpmPackage.PkgInfo.Name] = dependants
+		}
+
+		// Remove dependant packages from map if they are to be removed by this operation
+		for pkg, required := range packageDepndants {
+			required = slices.DeleteFunc(required, func(pkgName string) bool {
+				_, ok := packageDepndants[pkgName]
+				return ok
+			})
+			packageDepndants[pkg] = required
+		}
+
+		// Remove empty keys from map
+		maps.DeleteFunc(packageDepndants, func(pkg string, required []string) bool {
+			return len(required) == 0
+		})
+
+		// Return error
+		if len(packageDepndants) != 0 {
+			return nil, PackageRemovalDependencyErr{RequiredPackages: packageDepndants}
+		}
+	}
+
 	return operation, nil
 }