[PATCH v2] partial-clone: add a partial-clone test case

From: Abhradeep Chakraborty <chakrabortyabhradeep79@gmail.com>

In a blobless-cloned repo, `git log --follow -- <path>` (`<path>` have an exact OID rename) shouldn't download blob of the file from where the new file is renamed.

Add a test case to verify it.

Signed-off-by: Abhradeep Chakraborty <chakrabortyabhradeep79@gmail.com>
---
    partial-clone: add a partial-clone test case
    
    changes since v1:
    
     1. remove the event track method to detect the downloading as it is not
        future proof ( and buggy).
     2. Instead see if the file is missing initially and after running the
        git log --follow ... command.
    
    Fixes #827 [1]
    
    [1] https://github.com/gitgitgadget/git/issues/827

Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-1175%2FAbhra303%2Fcheck_partial_clone-v2
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-1175/Abhra303/check_partial_clone-v2
Pull-Request: https://github.com/gitgitgadget/git/pull/1175

Range-diff vs v1:

 1:  6b80b981977 ! 1:  52df433ad5e partial-clone: add a partial-clone test case
     @@ Commit message
          partial-clone: add a partial-clone test case
      
          In a blobless-cloned repo, `git log --follow -- <path>` (`<path>` have
     -    an exact OID rename) doesn't download blob of the file from where the
     +    an exact OID rename) shouldn't download blob of the file from where the
          new file is renamed.
      
          Add a test case to verify it.
     @@ t/t0410-partial-clone.sh: test_expect_success 'do not fetch when checking existe
       	git -C repo cherry-pick side1
       '
       
     -+test_expect_success 'git log --follow does not download blobs if an exact OID rename found (blobless clone)' '
     ++test_expect_success 'exact rename does not need to fetch the blob lazily' '
      +	rm -rf repo partial.git &&
      +	test_create_repo repo &&
      +	content="some dummy content" &&
      +	test_commit -C repo create-a-file file.txt "$content" &&
      +	git -C repo mv file.txt new-file.txt &&
      +	git -C repo commit -m rename-the-file &&
     ++	FILE_HASH=$(git -C repo rev-parse HEAD:new-file.txt) &&
      +	test_config -C repo uploadpack.allowfilter 1 &&
      +	test_config -C repo uploadpack.allowanysha1inwant 1 &&
      +
     -+	git clone --filter=blob:none "file://$(pwd)/repo" partial.git &&
     -+	GIT_TRACE2_EVENT="$(pwd)/trace.txt" \
     -+		git -C partial.git log --follow -- new-file.txt > "$(pwd)/trace.txt" &&
     -+	! test_subcommand_inexact fetch <trace.txt
     ++	git clone --filter=blob:none --bare "file://$(pwd)/repo" partial.git &&
     ++	git -C partial.git rev-list --objects --missing=print HEAD >out &&
     ++	grep "[?]$FILE_HASH" out &&
     ++	git -C partial.git log --follow -- new-file.txt &&
     ++	git -C partial.git rev-list --objects --missing=print HEAD >out &&
     ++	grep "[?]$FILE_HASH" out
      +'
      +
       test_expect_success 'lazy-fetch when accessing object not in the_repository' '
       	rm -rf full partial.git &&
       	test_create_repo full &&
     -
     - ## t/test-lib-functions.sh ##
     -@@ t/test-lib-functions.sh: test_subcommand_inexact () {
     - 		shift
     - 	fi
     - 
     --	local expr=$(printf '"%s".*' "$@")
     -+	local expr=$(printf '.*"%s".*' "$@")
     - 	expr="${expr%,}"
     - 
     - 	if test -n "$negate"

 t/t0410-partial-clone.sh | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)