[arch] improvement -> history/downgrade considering the repository commit + bug fixes

bauh/gems/arch/git.py

@@ -2,15 +2,12 @@ from datetime import datetime
 from typing import List, Tuple, Optional
 
 from bauh.commons import system
-from bauh.commons.system import new_subprocess
+from bauh.commons.system import new_subprocess, SimpleProcess
 
 
 def is_installed() -> bool:
-    try:
-        new_subprocess(['git', '--version'])
-        return True
-    except FileNotFoundError:
-        return False
+    code, _ = system.execute(cmd='which git', output=False)
+    return code == 0
 
 
 def list_commits(proj_dir: str) -> List[dict]:
@@ -30,6 +27,17 @@ def list_commits(proj_dir: str) -> List[dict]:
     return commits
 
 
+def get_current_commit(repo_path: str) -> Optional[str]:
+    code, output = system.execute(cmd='git log -1 --format=%H', shell=True, cwd=repo_path)
+
+    if code == 0:
+        for line in output.strip().split('\n'):
+            line_strip = line.strip()
+
+            if line_strip:
+                return line_strip
+
+
 def log_shas_and_timestamps(repo_path: str) -> Optional[List[Tuple[str, int]]]:
     code, output = system.execute(cmd='git log --format="%H %at"', shell=True, cwd=repo_path)
 
@@ -43,3 +51,12 @@ def log_shas_and_timestamps(repo_path: str) -> Optional[List[Tuple[str, int]]]:
                 logs.append((line_split[0].strip(), int(line_split[1].strip())))
 
         return logs
+
+
+def clone_as_process(url: str, cwd: Optional[str], depth: int = -1) -> SimpleProcess:
+    cmd = ['git', 'clone', url]
+
+    if depth > 0:
+        cmd.append('--depth={}'.format(depth))
+
+    return SimpleProcess(cmd=cmd, cwd=cwd)