common: update New*() functions to return interface type

Change the return types from pointers to the inheriting type (e.g.
'userProvider') to the interface type ('UserProvider'). This is more
consistent with the rest of the codebase, and more readily provides compiler
errors when the type does not implement the interface.

Signed-off-by: Victoria Dye <[email protected]>

Author: vdye

internal/common/command.go

@@ -11,7 +11,7 @@ type CommandExecutor interface {
 
 type commandExecutor struct{}
 
-func NewCommandExecutor() *commandExecutor {
+func NewCommandExecutor() CommandExecutor {
 	return &commandExecutor{}
 }
 

internal/common/filesystem.go

@@ -18,7 +18,7 @@ type FileSystem interface {
 
 type fileSystem struct{}
 
-func NewFileSystem() *fileSystem {
+func NewFileSystem() FileSystem {
 	return &fileSystem{}
 }
 

internal/common/user.go

@@ -10,7 +10,7 @@ type UserProvider interface {
 
 type userProvider struct{}
 
-func NewUserProvider() *userProvider {
+func NewUserProvider() UserProvider {
 	return &userProvider{}
 }