Currently, our default branch in tests is "master". This is the Git
default, but the Git default will likely change in the future, so it
makes sense to update our testsuite to be explicit about the branch
name. We'll ensure this continues by building against older versions of
Git as well as newer versions.
We use "main" for the new branch name, since that's the proposed value
upstream.
This commit was made entirely by automated means using the following
command:
git grep -l master t | xargs sed -i -e 's/master/main/g'
When we use git hash-object --stdin with the --path option, Git applies
filters to the object, so Git LFS is invoked. However, if the object
provided is less than 1024 bytes in size, we would hang. This occurred
because of our packet reader didn't quite implement the io.Reader
interface completely: if it returned a non-zero value and io.EOF, the
next call to Read would not return 0 and io.EOF. Instead, it would try
to read from stdin, which would not be sending us more data until we
provided a response, so we would hang.
To solve this, keep track of the EOF and always return it on subsequent
Read calls. In addition, don't process the callback to write the file
in this case, since we don't actually want to write into the working
tree.
The printf(1) command, like it's C cousin, takes a format string as its
first argument. If a shell variable is passed as the first argument, it
will be interpreted as a format string; this can lead to surprising
behavior and can cause the test suite to fail if we accidentally insert
a format string character into the variable.
Modify all the places in the individual tests that we use a plain quoted
variable as the format string by running the following Ruby one-liner:
ruby -i -pe '$_.gsub!(/printf "\$/, %q(printf "%s" "$))' t/t-*.sh
Avoid modifying the test helpers, as there are places (such as calc_oid)
where we want to pass text containing escapes (such as "\n") and have
those be properly interpreted by printf(1).
