Clean up file bulk-rename a little

- Rename command conventionally
- Optional input especially for globbing
- Add shorthand flags
- Run in parallel
- More tests

stdlib-candidate/std-rfc/batch-rename.nu

@@ -0,0 +1,41 @@
+# Rename a batch of files using a closure.
+#
+# The reason behind this command is quite simple:
+# - Sometimes one receives a bunch of files with integer ids: 1, 2, 3, ...
+# - These ids come rarely with padding... i.e. 1 instead of 001 when there are 3-digit ids
+# - This means that file with id 9 will be sorted way after file with id 1000
+#
+# This command allows to do such a task!
+#
+# Examples:
+#   Rename `.mise.toml` files to `.mise.local.toml` recursively
+#   > glob **/.mise.toml | batch-rename { str append .local }
+#
+#   Rename files in `/foo` with a name that has an id to have 3 digits with 0-padding
+#   > batch-rename --dir /foo {
+#      parse "some_format_{id}"
+#        | get 0
+#        | update id { fill --alignment r --character 0 --width 3 }
+#        | $"some_format_($in.id)"
+#    }
+export def main [
+    update_stem: closure, # The code to run on the stem of the files: should start with parsing the format and end with reconstructing the same format
+    --directory (-d): path, # The path where non-hidden files need to be renamed in bulk
+    --verbose (-v), # Be verbose when moving the files around
+]: nothing -> nothing {
+    let paths = if $directory == null {
+        $in
+    } else {
+        # ls instead of glob for hidden file behavior
+        ls --full-paths $directory | get name
+    }
+    if $paths == null {
+        error make { msg: 'batch-rename expects input paths or a valid --directory' }
+    }
+    $paths | par-each {
+        let old = $in
+        let new = $old | path parse | update stem $update_stem | path join
+        mv --force --verbose=$verbose $old $new
+    }
+    ignore
+}

stdlib-candidate/std-rfc/mod.nu

@@ -2,5 +2,5 @@
 export module record/
 export module str.nu
 # commands
-export use fs.nu *
+export use batch-rename.nu *
 export use set-env.nu *

stdlib-candidate/tests/batch-rename.nu

@@ -0,0 +1,62 @@
+use std assert
+use ../std-rfc 'batch-rename'
+
+const fixture = [
+    .gitignore
+    Cargo.toml
+    LICENSE
+    README.md
+    src
+    test.nu
+]
+
+export def 'test batch-rename --directory' [] {
+    test batch-rename {
+        batch-rename --directory $in { '_' + $in }
+    } --expects [
+        .gitignore # hidden by default
+        _Cargo.toml
+        _LICENSE
+        _README.md
+        _src
+        _test.nu
+    ]
+}
+
+export def 'test batch-rename where' [] {
+    test batch-rename {
+        glob ($in | path join *.*) | batch-rename { '_' + $in }
+    } --expects [
+        LICENSE # skip
+        _.gitignore
+        _Cargo.toml
+        _README.md
+        _test.nu
+        src # skip
+    ]
+}
+
+export def 'test batch-rename missing' [] {
+    assert error {
+        test batch-rename { ignore | batch-rename { '_' + $in } }
+    }
+}
+
+def 'test batch-rename' [
+    command: closure
+    --expects: list<string>
+] {
+    let test_dir = $nu.temp-path | path join (random uuid)
+    def actual-files [] {
+        ls --all --short-names $test_dir | get name | sort
+    }
+    # before
+    mkdir $test_dir
+    $fixture | each { |name| touch ($test_dir | path join $name) }
+    assert equal $fixture (actual-files)
+    # test
+    $test_dir | do $command
+    assert equal $expects (actual-files)
+    # after
+    rm --recursive --force $test_dir
+}

stdlib-candidate/tests/mod.nu

@@ -1,3 +1,3 @@
-export module fs.nu
+export module batch-rename.nu
 export module record.nu
 export module str.nu