Repositories: by default disable all units except code and pulls on forks (#22541)

Most of the time forks are used for contributing code only, so not
having
issues, projects, release and packages is a better default for such
cases.
They can still be enabled in the settings.

A new option `DEFAULT_FORK_REPO_UNITS` is added to configure the default
units on forks.

Also add missing `repo.packages` unit to documentation.

code by: @brechtvl

## :warning: BREAKING :warning: 

When forking a repository, the fork will now have issues, projects,
releases, packages and wiki disabled. These can be enabled in the
repository settings afterwards. To change back to the previous default
behavior, configure `DEFAULT_FORK_REPO_UNITS` to be the same value as
`DEFAULT_REPO_UNITS`.

Co-authored-by: Brecht Van Lommel <brecht@blender.org>

1 files changed, 38 insertions, 20 deletions

diff --git a/models/unit/unit.go b/models/unit/unit.go
index bcd0572ab9..a2a9079dc2 100644
--- a/models/unit/unit.go
+++ b/models/unit/unit.go
@@ -94,6 +94,12 @@ var (
 		TypePackages,
 	}
 
+	// ForkRepoUnits contains the default unit types for forks
+	DefaultForkRepoUnits = []Type{
+		TypeCode,
+		TypePullRequests,
+	}
+
 	// NotAllowedDefaultRepoUnits contains units that can't be default
 	NotAllowedDefaultRepoUnits = []Type{
 		TypeExternalWiki,
@@ -110,26 +116,41 @@ var (
 	DisabledRepoUnits = []Type{}
 )
 
-// LoadUnitConfig load units from settings
-func LoadUnitConfig() {
-	setDefaultRepoUnits := FindUnitTypes(setting.Repository.DefaultRepoUnits...)
-	// Default repo units set if setting is not empty
-	if len(setDefaultRepoUnits) > 0 {
+// Get valid set of default repository units from settings
+func validateDefaultRepoUnits(defaultUnits, settingDefaultUnits []Type) []Type {
+	units := defaultUnits
+
+	// Use setting if not empty
+	if len(settingDefaultUnits) > 0 {
 		// MustRepoUnits required as default
-		DefaultRepoUnits = make([]Type, len(MustRepoUnits))
-		copy(DefaultRepoUnits, MustRepoUnits)
-		for _, defaultU := range setDefaultRepoUnits {
-			if !defaultU.CanBeDefault() {
-				log.Warn("Not allowed as default unit: %s", defaultU.String())
+		units = make([]Type, len(MustRepoUnits))
+		copy(units, MustRepoUnits)
+		for _, settingUnit := range settingDefaultUnits {
+			if !settingUnit.CanBeDefault() {
+				log.Warn("Not allowed as default unit: %s", settingUnit.String())
 				continue
 			}
 			// MustRepoUnits already added
-			if defaultU.CanDisable() {
-				DefaultRepoUnits = append(DefaultRepoUnits, defaultU)
+			if settingUnit.CanDisable() {
+				units = append(units, settingUnit)
 			}
 		}
 	}
 
+	// Remove disabled units
+	for _, disabledUnit := range DisabledRepoUnits {
+		for i, unit := range units {
+			if unit == disabledUnit {
+				units = append(units[:i], units[i+1:]...)
+			}
+		}
+	}
+
+	return units
+}
+
+// LoadUnitConfig load units from settings
+func LoadUnitConfig() {
 	DisabledRepoUnits = FindUnitTypes(setting.Repository.DisabledRepoUnits...)
 	// Check that must units are not disabled
 	for i, disabledU := range DisabledRepoUnits {
@@ -138,14 +159,11 @@ func LoadUnitConfig() {
 			DisabledRepoUnits = append(DisabledRepoUnits[:i], DisabledRepoUnits[i+1:]...)
 		}
 	}
-	// Remove disabled units from default units
-	for _, disabledU := range DisabledRepoUnits {
-		for i, defaultU := range DefaultRepoUnits {
-			if defaultU == disabledU {
-				DefaultRepoUnits = append(DefaultRepoUnits[:i], DefaultRepoUnits[i+1:]...)
-			}
-		}
-	}
+
+	setDefaultRepoUnits := FindUnitTypes(setting.Repository.DefaultRepoUnits...)
+	DefaultRepoUnits = validateDefaultRepoUnits(DefaultRepoUnits, setDefaultRepoUnits)
+	setDefaultForkRepoUnits := FindUnitTypes(setting.Repository.DefaultForkRepoUnits...)
+	DefaultForkRepoUnits = validateDefaultRepoUnits(DefaultForkRepoUnits, setDefaultForkRepoUnits)
 }
 
 // UnitGlobalDisabled checks if unit type is global disabled