Add JSONDecodeError handling for get_lockfile_hash

Now will return None when facing JSONDecodeError when loading the lockfile.

do_init will remove the old lockfile and replace it.

pipenv/core.py

@@ -1257,6 +1257,26 @@ def do_init(
                     ),
                     err=True,
                 )
+            elif old_hash is None:
+                # Lockfile corrupted, remove it and replaced
+                click.echo(
+                    crayons.red(
+                        u"Pipfile.lock is corrupted, replaced with ({0})…".format(
+                            new_hash[-6:]
+                        ),
+                        bold=True,
+                    ),
+                    err=True
+                )
+                os.remove(project.lockfile_location)
+                do_lock(
+                    system=system,
+                    pre=pre,
+                    keep_outdated=keep_outdated,
+                    verbose=verbose,
+                    write=True,
+                    pypi_mirror=pypi_mirror,
+                )
             else:
                 click.echo(
                     crayons.red(

pipenv/project.py

@@ -815,7 +815,11 @@ class Project(object):
         if not os.path.exists(self.lockfile_location):
             return
 
-        lockfile = self.load_lockfile(expand_env_vars=False)
+        try:
+            lockfile = self.load_lockfile(expand_env_vars=False)
+        except json.decoder.JSONDecodeError:
+            # Lockfile corrupted
+            return
         if "_meta" in lockfile and hasattr(lockfile, "keys"):
             return lockfile["_meta"].get("hash", {}).get("sha256")
         # Lockfile exists but has no hash at all

tests/integration/test_lock.py

@@ -385,3 +385,25 @@ django = "*"
         django_version = '==2.0.6' if py_version.startswith('3') else '==1.11.13'
         assert py_version == '2.7.14'
         assert p.lockfile['default']['django']['version'] == django_version
+
+
+@pytest.mark.lock
+@pytest.mark.install
+def test_lockfile_corrupted(PipenvInstance):
+    with PipenvInstance() as p:
+        with open(p.lockfile_path, 'w') as f:
+            f.write('{corrupt}')
+        c = p.pipenv('install')
+        assert c.return_code == 0
+        assert p.lockfile['_meta']
+
+
+@pytest.mark.lock
+@pytest.mark.install
+def test_lockfile_with_empty_dict(PipenvInstance):
+    with PipenvInstance() as p:
+        with open(p.lockfile_path, 'w') as f:
+            f.write('{}')
+        c = p.pipenv('install')
+        assert c.return_code == 0
+        assert p.lockfile['_meta']