New revision_mode = scm_folder for monorepos (#13562)

* changing revision_mode=scm base folder

* wip

conans/client/cmd/export.py

@@ -84,7 +84,7 @@ def cmd_export(app, conanfile_path, name, version, user, channel, graph_lock=Non
 
 
 def _calc_revision(scoped_output, path, manifest, revision_mode):
-    if revision_mode not in ["scm", "hash"]:
+    if revision_mode not in ["scm", "scm_folder", "hash"]:
         raise ConanException("Revision mode should be one of 'hash' (default) or 'scm'")
 
     # Use the proper approach depending on 'revision_mode'
@@ -93,7 +93,8 @@ def _calc_revision(scoped_output, path, manifest, revision_mode):
     else:
         try:
             with chdir(path):
-                rev_detected = check_output_runner('git rev-list HEAD -n 1 --full-history').strip()
+                f = '-- "."' if revision_mode == "scm_folder" else ""
+                revision = check_output_runner(f'git rev-list HEAD -n 1 --full-history {f}').strip()
         except Exception as exc:
             error_msg = "Cannot detect revision using '{}' mode from repository at " \
                         "'{}'".format(revision_mode, path)
@@ -104,8 +105,6 @@ def _calc_revision(scoped_output, path, manifest, revision_mode):
                 raise ConanException("Can't have a dirty repository using revision_mode='scm' and doing"
                                      " 'conan export', please commit the changes and run again.")
 
-        revision = rev_detected
-
         scoped_output.info("Using git commit as the recipe revision: %s" % revision)
 
     return revision

conans/test/functional/command/export_test.py

@@ -1,30 +1,66 @@
-import textwrap
-import unittest
+import os
 
 import pytest
 
 from conans.model.recipe_ref import RecipeReference
+from conans.test.assets.genconanfile import GenConanfile
+from conans.test.utils.scm import git_add_changes_commit
 from conans.test.utils.tools import TestClient
 
 
-class ExportMetadataTest(unittest.TestCase):
-    conanfile = textwrap.dedent("""
-        from conan import ConanFile
+@pytest.mark.tool("git")
+class TestRevisionModeSCM:
 
-        class Lib(ConanFile):
-            revision_mode = "{revision_mode}"
-    """)
+    def test_revision_mode_scm(self):
+        t = TestClient()
+        conanfile = str(GenConanfile().with_class_attribute('revision_mode = "scm"'))
+        commit = t.init_git_repo({'conanfile.py': conanfile})
 
-    summary_hash = "bfe8b4a6a2a74966c0c4e0b34705004a"
+        t.run(f"export . --name=pkg --version=0.1")
 
-    @pytest.mark.tool("git")
-    def test_revision_mode_scm(self):
+        ref = RecipeReference.loads("pkg/0.1")
+        latest_rev = t.cache.get_latest_recipe_reference(ref)
+        assert latest_rev.revision == commit
+
+        # Now it will fail if dirty
+        t.save({"conanfile.py": conanfile + "\n#comment"})
+        t.run(f"export . --name=pkg --version=0.1", assert_error=True)
+        assert "Can't have a dirty repository using revision_mode='scm' and doing" in t.out
+        # Commit to fix
+        commit2 = git_add_changes_commit(t.current_folder, msg="fix")
+        t.run(f"export . --name=pkg --version=0.1")
+        latest_rev = t.cache.get_latest_recipe_reference(ref)
+        assert latest_rev.revision == commit2
+
+    def test_revision_mode_scm_subfolder(self):
+        """ emulates a mono-repo with 2 subprojects, when a change is done in a subproject
+        it gets a different folder commit
+        """
         t = TestClient()
-        commit = t.init_git_repo({'conanfile.py': self.conanfile.format(revision_mode="scm")})
+        conanfile = str(GenConanfile().with_class_attribute('revision_mode = "scm_folder"'))
+        commit = t.init_git_repo({'pkga/conanfile.py': conanfile,
+                                  'pkgb/conanfile.py': conanfile})
 
-        ref = RecipeReference.loads("name/version@user/channel")
-        t.run(f"export . --name={ref.name} --version={ref.version} --user={ref.user} --channel={ref.channel}")
+        t.save({"pkgb/conanfile.py": conanfile + "\n#comment"})
+        commit_b = git_add_changes_commit(os.path.join(t.current_folder, "pkgb"), msg="fix")
 
+        # pkga still gets the initial commit, as it didn't change its contents
+        t.run(f"export pkga --name=pkga --version=0.1")
+        ref = RecipeReference.loads("pkga/0.1")
         latest_rev = t.cache.get_latest_recipe_reference(ref)
+        assert latest_rev.revision == commit
 
-        self.assertEqual(latest_rev.revision, commit)
+        # but pkgb will get the commit of the new changed folder
+        t.run(f"export pkgb --name=pkgb --version=0.1")
+        ref = RecipeReference.loads("pkgb/0.1")
+        latest_rev = t.cache.get_latest_recipe_reference(ref)
+        assert latest_rev.revision == commit_b
+
+    def test_auto_revision_without_commits(self):
+        """If we have a repo but without commits, it has to fail when the revision_mode=scm"""
+        t = TestClient()
+        t.run_command('git init .')
+        t.save({"conanfile.py": GenConanfile("lib", "0.1").with_revision_mode("scm")})
+        t.run("export .", assert_error=True)
+        # It errors, because no commits yet
+        assert "Cannot detect revision using 'scm' mode from repository" in t.out

conans/test/functional/revisions_test.py

@@ -796,35 +796,6 @@ def test_upload_no_overwrite_packages(self):
                          pref2.revision)
 
 
-class SCMRevisions(unittest.TestCase):
-
-    def test_auto_revision_even_without_scm_git(self):
-        """
-        Can't do conan create/export with uncommited changes if using revision_mode=scm
-        """
-        ref = RecipeReference.loads("lib/1.0@conan/testing")
-        client = TurboTestClient()
-        conanfile = GenConanfile().with_revision_mode("scm")
-        commit = client.init_git_repo(files={"file.txt": "hey", "conanfile.py": str(conanfile)},
-                                      origin_url="http://myrepo.git")
-        client.create(ref, conanfile=conanfile)
-        self.assertEqual(client.recipe_revision(ref), commit)
-
-        # Change the conanfile and make another create, the revision should be the same
-        client.save({"conanfile.py": str(conanfile.with_build_msg("New changes!"))})
-        client.create(ref, conanfile=conanfile, assert_error=True)
-        self.assertIn("Can't have a dirty repository using revision_mode='scm' and doing", client.out)
-
-    def test_auto_revision_without_commits(self):
-        """If we have a repo but without commits, it has to fail when the revision_mode=scm"""
-        client = TurboTestClient()
-        client.run_command('git init .')
-        client.save({"conanfile.py": GenConanfile("lib", "0.1").with_revision_mode("scm")})
-        client.run("create .", assert_error=True)
-        # It error, because the revision_mode is explicitly set to scm
-        self.assertIn("Cannot detect revision using 'scm' mode from repository", client.out)
-
-
 class CapabilitiesRevisionsTest(unittest.TestCase):
     def test_server_with_only_v2_capability(self):
         server = TestServer(server_capabilities=[])