How to grab commit from grep output-CodePudding

Say I call the following command in a git repo:

git log --oneline -n 10 | grep pattern

and it gives me the following output:

c95383f asdfasdf pattern
3e34762 asdfasdfsd pattern

How can I grab just the commit hash from the second line so that I can pipe it into another command?

CodePudding user response：

You can consider awk for this:

git log --oneline -n 10 | awk '/pattern/ {print $1}'

Where /pattern/ matches pattern in a line while {print $1} prints first field from a matching line.

CodePudding user response：

My friend just showed me this:

git log --oneline -n 10 | grep pattern | awk 'END{print $1}'

But I'm interested to see if anyone has any different solutions.

CodePudding user response：

For the commits printed (ten in this case), print the hash of the oldest commit matching pattern:

git log --oneline -n 10 |
awk '$0 ~ /pattern/ {hash = $1} END {print hash}'

Same, but for the Nth newest:

git log --oneline -n 10 |
awk '$0 ~ /pattern/ &&   c==N {print $1}'

(use 1 for newest, or 2 for second newest, etc, N must be <= 10 in this example)

Print hash of Nth newest commit (no pattern):

git log --oneline -n N |
awk 'END {print $1}'

git log --oneline |
awk 'NR==N {print $1}'

Remember that git log has the options --since, --after, --until, and --before, which take a date as input.