add category cmd line option

pipenv/cli/command.py

@@ -1,3 +1,4 @@
+from gc import is_finalized
 import os
 import sys
 
@@ -85,7 +86,7 @@ def cli(
 
     load_dot_env(state.project, quiet=state.quiet)
 
-    from ..core import (
+    from pipenv.core import (
         cleanup_virtualenv,
         do_clear,
         do_py,
@@ -740,8 +741,9 @@ def verify(state):
 )
 @option("--hash", is_flag=True, default=False, help="Add package hashes.")
 @option("--exclude-markers", is_flag=True, default=False, help="Exclude markers.")
+@option("--category", is_flag=False, default='', help="Only add requirement of the specified category.")
 @pass_state
-def requirements(state, dev=False, dev_only=False, hash=False, exclude_markers=False):
+def requirements(state, dev=False, dev_only=False, hash=False, exclude_markers=False, category=''):
 
     from pipenv.utils.dependencies import convert_deps_to_pip
 
@@ -753,10 +755,13 @@ def requirements(state, dev=False, dev_only=False, hash=False, exclude_markers=F
 
     deps = {}
 
-    if dev or dev_only:
-        deps.update(lockfile["develop"])
-    if not dev_only:
-        deps.update(lockfile["default"])
+    if category:
+        deps.update(lockfile.get(category, {}))
+    else:
+        if dev or dev_only:
+            deps.update(lockfile["develop"])
+        if not dev_only:
+            deps.update(lockfile["default"])
 
     pip_deps = convert_deps_to_pip(
         deps,

tests/integration/test_requirements.py

@@ -72,6 +72,41 @@ def test_requirements_generates_requirements_from_lockfile_multiple_sources(pipe
         assert '--extra-index-url https://some_other_source.org' in c.stdout
 
 
+@pytest.mark.requirements
+def test_requirements_generates_requirements_from_lockfile_from_a_category(pipenv_instance_private_pypi):
+    with pipenv_instance_private_pypi(chdir=True) as p:
+        packages = ('six', '1.12.0')
+        dev_packages = ('itsdangerous', '1.1.0')
+        test_packages = ('pytest', '7.1.3')
+        with open(p.pipfile_path, 'w') as f:
+            contents = f"""
+            [[source]]
+            name = "pypi"
+            url = "https://pypi.org/simple"
+            verify_ssl = true
+            [packages]
+            {packages[0]}= "=={packages[1]}"
+            [dev-packages]
+            {dev_packages[0]}= "=={dev_packages[1]}"
+            [test-packages]
+            {test_packages[0]}= "=={test_packages[1]}"
+            """.strip()
+            f.write(contents)
+        l = p.pipenv('lock')
+        assert l.returncode == 0
+        
+        c = p.pipenv('requirements --dev-only')
+        assert c.returncode == 0
+        assert f'{packages[0]}=={packages[1]}' not in c.stdout
+        assert f'{test_packages[0]}=={test_packages[1]}' not in c.stdout
+        assert f'{dev_packages[0]}=={dev_packages[1]}' in c.stdout
+
+        d = p.pipenv('requirements --category test')
+        assert d.returncode == 0
+        assert f'{packages[0]}=={packages[1]}' not in d.stdout
+        assert f'{dev_packages[0]}=={dev_packages[1]}' not in c.stdout
+        assert f'{test_packages[0]}=={test_packages[1]}' in d.stdout
+
 @pytest.mark.requirements
 def test_requirements_with_git_requirements(pipenv_instance_pypi):
     req_name, req_hash = 'example-repo', 'cc858e89f19bc0dbd70983f86b811ab625dc9292'