Fixes #4516 file module: check prev_state earlier and use that if state is not specified

library/files/file

@@ -142,7 +142,7 @@ def main():
 
     module = AnsibleModule(
         argument_spec = dict(
-            state = dict(choices=['file','directory','link','hard','touch','absent'], default='file'),
+            state = dict(choices=['file','directory','link','hard','touch','absent'], default=None),
             path  = dict(aliases=['dest', 'name'], required=True),
             recurse  = dict(default='no', type='bool'),
             force = dict(required=False,default=False,type='bool'),
@@ -171,6 +171,30 @@ def main():
             pass
         module.exit_json(path=path, changed=False, appears_binary=appears_binary)
 
+    prev_state = 'absent'
+
+    if os.path.lexists(path):
+        if os.path.islink(path):
+            prev_state = 'link'
+        elif os.path.isdir(path):
+            prev_state = 'directory'
+        elif os.stat(path).st_nlink > 1:
+            prev_state = 'hard'
+        else:
+            # could be many other things, but defaulting to file
+            prev_state = 'file'
+
+    if prev_state is not None and state is None:
+        if not params.get('src', None):
+            # idempotent exit if state is not specified
+            module.exit_json(path=path, changed=False)
+        else:
+            # src is defined, need to process other operations
+            state = prev_state
+    elif state is None:
+        # set default state to file
+        state = 'file'
+
     # source is both the source of a symlink or an informational passing of the src for a template module
     # or copy module, even if this module never uses it, it is needed to key off some things
 
@@ -190,19 +214,6 @@ def main():
 
     changed = False
 
-    prev_state = 'absent'
-
-    if os.path.lexists(path):
-        if os.path.islink(path):
-            prev_state = 'link'
-        elif os.path.isdir(path):
-            prev_state = 'directory'
-        elif os.stat(path).st_nlink > 1:
-            prev_state = 'hard'
-        else:
-            # could be many other things, but defaulting to file
-            prev_state = 'file'
-
     recurse = params['recurse']
 
     if recurse and state == 'file' and prev_state == 'directory':