Merge branch 'jk/interop-test'
Picking two versions of Git and running tests to make sure the
older one and the newer one interoperate happily has now become
possible.
* jk/interop-test:
t/interop: add test of old clients against modern git-daemon
t: add an interoperability test harness
diff --git a/Makefile b/Makefile
index ed68700..ba524f3 100644
--- a/Makefile
+++ b/Makefile
@@ -2251,6 +2251,9 @@
ifdef GIT_PERF_MAKE_OPTS
@echo GIT_PERF_MAKE_OPTS=\''$(subst ','\'',$(subst ','\'',$(GIT_PERF_MAKE_OPTS)))'\' >>$@+
endif
+ifdef GIT_INTEROP_MAKE_OPTS
+ @echo GIT_INTEROP_MAKE_OPTS=\''$(subst ','\'',$(subst ','\'',$(GIT_INTEROP_MAKE_OPTS)))'\' >>$@+
+endif
ifdef TEST_GIT_INDEX_VERSION
@echo TEST_GIT_INDEX_VERSION=\''$(subst ','\'',$(subst ','\'',$(TEST_GIT_INDEX_VERSION)))'\' >>$@+
endif
diff --git a/t/interop/.gitignore b/t/interop/.gitignore
new file mode 100644
index 0000000..49c78d3
--- /dev/null
+++ b/t/interop/.gitignore
@@ -0,0 +1,4 @@
+/trash directory*/
+/test-results/
+/.prove/
+/build/
diff --git a/t/interop/Makefile b/t/interop/Makefile
new file mode 100644
index 0000000..31a4bbc
--- /dev/null
+++ b/t/interop/Makefile
@@ -0,0 +1,16 @@
+-include ../../config.mak
+export GIT_TEST_OPTIONS
+
+SHELL_PATH ?= $(SHELL)
+SHELL_PATH_SQ = $(subst ','\'',$(SHELL_PATH))
+T = $(sort $(wildcard i[0-9][0-9][0-9][0-9]-*.sh))
+
+all: $(T)
+
+$(T):
+ @echo "*** $@ ***"; '$(SHELL_PATH_SQ)' $@ $(GIT_TEST_OPTS)
+
+clean:
+ rm -rf build "trash directory".* test-results
+
+.PHONY: all clean $(T)
diff --git a/t/interop/README b/t/interop/README
new file mode 100644
index 0000000..72d42bd
--- /dev/null
+++ b/t/interop/README
@@ -0,0 +1,85 @@
+Git version interoperability tests
+==================================
+
+This directory has interoperability tests for git. Each script is
+similar to the normal test scripts found in t/, but with the added twist
+that two special versions of git, "git.a" and "git.b", are available in
+the PATH. Individual tests can then check the interaction between the
+two versions.
+
+When you add a feature that handles backwards compatibility between git
+versions, it's encouraged to add a test here to make sure it behaves as
+you expect.
+
+
+Running Tests
+-------------
+
+The easiest way to run tests is to say "make". This runs all
+the tests against their default versions.
+
+You can run a single test like:
+
+ $ ./i0000-basic.sh
+ ok 1 - bare git is forbidden
+ ok 2 - git.a version (v1.6.6.3)
+ ok 3 - git.b version (v2.11.1)
+ # passed all 3 test(s)
+ 1..3
+
+Each test contains default versions to run against. You may override
+these by setting `GIT_TEST_VERSION_A` and `GIT_TEST_VERSION_B` in the
+environment. Note that not all combinations will give sensible outcomes
+for all tests (e.g., a test checking for a specific old/new interaction
+may want something "old" enough" and something "new" enough; see
+individual tests for details).
+
+Version names should be resolvable as revisions in the current
+repository. They will be exported and built as needed using the
+config.mak files found at the root of your working tree.
+
+The exception is the special version "." which uses the currently-built
+contents of your working tree.
+
+You can set the following variables (in the environment or in your config.mak):
+
+ GIT_INTEROP_MAKE_OPTS
+ Options to pass to `make` when building a git version (e.g.,
+ `-j8`).
+
+You can also pass any command-line options taken by ordinary git tests (e.g.,
+"-v").
+
+
+Naming Tests
+------------
+
+The interop test files are named like:
+
+ iNNNN-short-description.sh
+
+where N is a decimal digit. The same conventions for choosing NNNN as
+for normal tests apply.
+
+
+Writing Tests
+-------------
+
+An interop test script starts like a normal script, declaring a few
+variables and then including interop-lib.sh (which includes test-lib.sh).
+Besides test_description, you should also set the $VERSION_A and $VERSION_B
+variables to give the default versions to test against. See t0000-basic.sh for
+an example.
+
+You can then use test_expect_success as usual, with a few differences:
+
+ 1. The special commands "git.a" and "git.b" correspond to the
+ two versions.
+
+ 2. You cannot call a bare "git". This is to prevent accidents where
+ you meant "git.a" or "git.b".
+
+ 3. The trash directory is _not_ a git repository by default. You
+ should create one with the appropriate version of git.
+
+At the end of the script, call test_done as usual.
diff --git a/t/interop/i0000-basic.sh b/t/interop/i0000-basic.sh
new file mode 100755
index 0000000..903e919
--- /dev/null
+++ b/t/interop/i0000-basic.sh
@@ -0,0 +1,27 @@
+#!/bin/sh
+
+# Note that this test only works on real version numbers,
+# as it depends on matching the output to "git version".
+VERSION_A=v1.6.6.3
+VERSION_B=v2.11.1
+
+test_description='sanity test interop library'
+. ./interop-lib.sh
+
+test_expect_success 'bare git is forbidden' '
+ test_must_fail git version
+'
+
+test_expect_success "git.a version ($VERSION_A)" '
+ echo git version ${VERSION_A#v} >expect &&
+ git.a version >actual &&
+ test_cmp expect actual
+'
+
+test_expect_success "git.b version ($VERSION_B)" '
+ echo git version ${VERSION_B#v} >expect &&
+ git.b version >actual &&
+ test_cmp expect actual
+'
+
+test_done
diff --git a/t/interop/i5500-git-daemon.sh b/t/interop/i5500-git-daemon.sh
new file mode 100755
index 0000000..1daf694
--- /dev/null
+++ b/t/interop/i5500-git-daemon.sh
@@ -0,0 +1,41 @@
+#!/bin/sh
+
+VERSION_A=.
+VERSION_B=v1.0.0
+
+: ${LIB_GIT_DAEMON_PORT:=5500}
+LIB_GIT_DAEMON_COMMAND='git.a daemon'
+
+test_description='clone and fetch by older client'
+. ./interop-lib.sh
+. "$TEST_DIRECTORY"/lib-git-daemon.sh
+
+start_git_daemon --export-all
+
+repo=$GIT_DAEMON_DOCUMENT_ROOT_PATH/repo
+
+test_expect_success "create repo served by $VERSION_A" '
+ git.a init "$repo" &&
+ git.a -C "$repo" commit --allow-empty -m one
+'
+
+test_expect_success "clone with $VERSION_B" '
+ git.b clone "$GIT_DAEMON_URL/repo" child &&
+ echo one >expect &&
+ git.a -C child log -1 --format=%s >actual &&
+ test_cmp expect actual
+'
+
+test_expect_success "fetch with $VERSION_B" '
+ git.a -C "$repo" commit --allow-empty -m two &&
+ (
+ cd child &&
+ git.b fetch
+ ) &&
+ echo two >expect &&
+ git.a -C child log -1 --format=%s FETCH_HEAD >actual &&
+ test_cmp expect actual
+'
+
+stop_git_daemon
+test_done
diff --git a/t/interop/interop-lib.sh b/t/interop/interop-lib.sh
new file mode 100644
index 0000000..3e0a291
--- /dev/null
+++ b/t/interop/interop-lib.sh
@@ -0,0 +1,92 @@
+# Interoperability testing framework. Each script should source
+# this after setting default $VERSION_A and $VERSION_B variables.
+
+. ../../GIT-BUILD-OPTIONS
+INTEROP_ROOT=$(pwd)
+BUILD_ROOT=$INTEROP_ROOT/build
+
+build_version () {
+ if test -z "$1"
+ then
+ echo >&2 "error: test script did not set default versions"
+ return 1
+ fi
+
+ if test "$1" = "."
+ then
+ git rev-parse --show-toplevel
+ return 0
+ fi
+
+ sha1=$(git rev-parse "$1^{tree}") || return 1
+ dir=$BUILD_ROOT/$sha1
+
+ if test -e "$dir/.built"
+ then
+ echo "$dir"
+ return 0
+ fi
+
+ echo >&2 "==> Building $1..."
+
+ mkdir -p "$dir" || return 1
+
+ (cd "$(git rev-parse --show-cdup)" && git archive --format=tar "$sha1") |
+ (cd "$dir" && tar x) ||
+ return 1
+
+ for config in config.mak config.mak.autogen config.status
+ do
+ if test -e "$INTEROP_ROOT/../../$config"
+ then
+ cp "$INTEROP_ROOT/../../$config" "$dir/" || return 1
+ fi
+ done
+
+ (
+ cd "$dir" &&
+ make $GIT_INTEROP_MAKE_OPTS >&2 &&
+ touch .built
+ ) || return 1
+
+ echo "$dir"
+}
+
+# Old versions of git don't have bin-wrappers, so let's give a rough emulation.
+wrap_git () {
+ write_script "$1" <<-EOF
+ GIT_EXEC_PATH="$2"
+ export GIT_EXEC_PATH
+ PATH="$2:\$PATH"
+ export GIT_EXEC_PATH
+ exec git "\$@"
+ EOF
+}
+
+generate_wrappers () {
+ mkdir -p .bin &&
+ wrap_git .bin/git.a "$DIR_A" &&
+ wrap_git .bin/git.b "$DIR_B" &&
+ write_script .bin/git <<-\EOF &&
+ echo >&2 fatal: test tried to run generic git
+ exit 1
+ EOF
+ PATH=$(pwd)/.bin:$PATH
+}
+
+VERSION_A=${GIT_TEST_VERSION_A:-$VERSION_A}
+VERSION_B=${GIT_TEST_VERSION_B:-$VERSION_B}
+
+if ! DIR_A=$(build_version "$VERSION_A") ||
+ ! DIR_B=$(build_version "$VERSION_B")
+then
+ echo >&2 "fatal: unable to build git versions"
+ exit 1
+fi
+
+TEST_DIRECTORY=$INTEROP_ROOT/..
+TEST_OUTPUT_DIRECTORY=$INTEROP_ROOT
+TEST_NO_CREATE_REPO=t
+. "$TEST_DIRECTORY"/test-lib.sh
+
+generate_wrappers || die "unable to set up interop test environment"
diff --git a/t/lib-git-daemon.sh b/t/lib-git-daemon.sh
index f9cbd47..987d406 100644
--- a/t/lib-git-daemon.sh
+++ b/t/lib-git-daemon.sh
@@ -46,7 +46,8 @@
say >&3 "Starting git daemon ..."
mkfifo git_daemon_output
- git daemon --listen=127.0.0.1 --port="$LIB_GIT_DAEMON_PORT" \
+ ${LIB_GIT_DAEMON_COMMAND:-git daemon} \
+ --listen=127.0.0.1 --port="$LIB_GIT_DAEMON_PORT" \
--reuseaddr --verbose \
--base-path="$GIT_DAEMON_DOCUMENT_ROOT_PATH" \
"$@" "$GIT_DAEMON_DOCUMENT_ROOT_PATH" \
