add checksum_cmd directive to command

docs/docs/changelog.md

@@ -5,73 +5,6 @@ title: Changelog
 
 ## [Unreleased](https://github.com/lets-cli/lets/releases/tag/v0.0.X)
 
-* `[Dependency]` update go to `1.26`
-* `[Added]` Show similar command suggestions on typos.
-* `[Changed]` Exit code 2 on unknown command.
-* `[Added]` Expose `LETS_OS` and `LETS_ARCH` environment variables at command runtime.
-* `[Removed]` Drop deprecated `eval_env` directive. Use `env` with `sh` execution mode instead.
-* `[Added]` When a command or its `depends` chain fails, print an indented tree to stderr showing the full chain with the failing command highlighted
-* `[Added]` Support `env_file` in global config and commands. File names are expanded after `env` is resolved, and values loaded from env files override values from `env`.
-* `[Changed]` Migrate the LSP YAML parser from the CGO-based tree-sitter bindings to pure-Go [`gotreesitter`](https://github.com/odvcencio/gotreesitter), removing the C toolchain requirement from normal builds and release packaging.
-
-## [0.0.59](https://github.com/lets-cli/lets/releases/tag/v0.0.59)
-
-* `[Fixed]` Fixed indentation issues for long commands in help output. Command names are now properly padded for consistent alignment.
-* `[Refactoring]` Refactored `maxCommandNameLen` to use `slices.MaxFunc` with proper handling for empty command lists.
-
-## [0.0.58](https://github.com/lets-cli/lets/releases/tag/v0.0.58)
-
-* `[Added]` `group` directive for commands. Organize commands into groups for better readability in help output. See [config reference for group](/docs/config#group).
-
-  ```yaml
-  commands:
-    build:
-      group: Development
-      cmd: npm run build
-
-    test:
-      group: Development
-      cmd: npm test
-
-    deploy:
-      group: Operations
-      cmd: ./deploy.sh
-  ```
-
-## [0.0.57](https://github.com/lets-cli/lets/releases/tag/v0.0.57)
-
-* `[Dependency]` update go to `1.24`
-* `[Added]` support custom top-level keywords that start with `x-`
-* `[Added]` check for invalid top-level keywords during config parsing
-* `[Added]` support YAML aliases in `env` - env will be merged aliases mapping
-
-## [0.0.56](https://github.com/lets-cli/lets/releases/tag/v0.0.56)
-
-This tag is not released due to build issues
-
-## [0.0.55](https://github.com/lets-cli/lets/releases/tag/v0.0.55)
-
-* `[Added]` `lets self` command that is ment to be a new home for all lets own commands such as `completions` (soon) or `lsp`
-* `[Added]` `lets self lsp` command that starts built-in `lsp` server with go to definition support and completions
-* [`Development`] Since `lsp` implementation uses  `https://tree-sitter.github.io` (C library with go bindings) as a internal parser `lets` now build with `CGO_ENABLED=1`. If you are building on local machine, you do not have to specify `CGO_ENABLED` env variable. But you may have to install some build system dependencies in case compilatino fails.
-* `[CI]` reworked release pipeline now supports go cross compilation
-* `[Improvment]` split commands in help message into `Commands` and `Internal commands`
-* `[Dependency]` update go to `1.23`
-* `[Dependency]` update goreleaser to `1.63.x`
-* `[Dependency]` update golangci-lint to `2.x` (also applied some lint fixes across codebase)
-
-## [0.0.54](https://github.com/lets-cli/lets/releases/tag/v0.0.54)
-
-* `[Fixed]` `lets --init` now properly creates `lets.yaml`. Issue [#263](https://github.com/lets-cli/lets/issues/263)
-* `[Dependency]` update go to `1.22`
-* `[Fixed]` ensure `init` script does not get called twice. Issue [#256](https://github.com/lets-cli/lets/issues/256)
-* `[Fixed]` do not fail if `sh` in env is empty. Issue [#235](https://github.com/lets-cli/lets/issues/235)
-* `[Fixed]` support `arm64` in `lets --upgrade`. Issue [#254](https://github.com/lets-cli/lets/issues/254)
-
-## [0.0.53](https://github.com/lets-cli/lets/releases/tag/v0.0.53)
-
-* `[Fixed]` change `SHELL` env to `LETS_SHELL` because setting system variable `SHELL` to just `bash` without full path to binary cases and error in some cases.
-
 ## [0.0.52](https://github.com/lets-cli/lets/releases/tag/v0.0.52)
 
 * `[Dependency]` update and pin goreleaser

docs/docs/config.md

@@ -3,35 +3,25 @@ id: config
 title: Config reference
 ---
 
-- [Top-level directives:](#top-level-directives)
-  - [Version](#version)
-  - [Shell](#shell)
-  - [Global env](#global-env)
-  - [Global before](#global-before)
-  - [Global init](#global-init)
-    - [Conditional init](#conditional-init)
-  - [Mixins](#mixins)
-  - [Ignored mixins](#ignored-mixins)
-  - [Remote mixins `(experimental)`](#remote-mixins-experimental)
-  - [Commands](#commands)
-- [Command directives:](#command-directives)
-  - [Short syntax](#short-syntax)
-  - [`cmd`](#cmd)
-  - [`description`](#description)
-  - [`work_dir`](#work_dir)
-  - [`shell`](#shell-1)
-  - [`after`](#after)
-  - [`depends`](#depends)
-    - [Override arguments in depends command](#override-arguments-in-depends-command)
-  - [`options`](#options)
-  - [`env`](#env)
-  - [`checksum`](#checksum)
-  - [`persist_checksum`](#persist_checksum)
-  - [`ref`](#ref)
-  - [`args`](#args)
-  - [`group`](#group)
-- [Aliasing:](#aliasing)
-  - [Env aliasing](#env-aliasing)
+* [shell](#shell)
+* [mixins](#mixins)
+* [env](#global-env)
+* [eval_env](#global-eval_env)
+* [init](#global-init)
+* [before](#global-before)
+* [commands](#commands)
+    * [description](#description)
+    * [cmd](#cmd)
+    * [work_dir](#work_dir)
+    * [after](#after)
+    * [depends](#depends)
+    * [options](#options)
+    * [env](#env)
+    * [eval_env](#eval_env)
+    * [checksum](#checksum)
+    * [persist_checksum](#persist_checksum)
+    * [ref](#ref)
+    * [args](#args)
 
 
 ## Top-level directives:
@@ -843,6 +833,31 @@ commands:
       docker run --rm myrepo/app${LETS_CHECKSUM} python -m app
 ```
 
+### `checksum_cmd`
+
+`key: checksum_cmd`
+
+`type: string`
+
+Use `checksum_cmd` when checksum should come from a shell command instead of a list of files.
+
+The command runs with the same effective `shell` and `work_dir` as the command itself, so command-level overrides apply here too.
+
+Result then can be accessed via `LETS_CHECKSUM` env variable.
+
+Example:
+
+```yaml
+shell: sh
+
+commands:
+  build-image:
+    shell: bash
+    work_dir: backend
+    checksum_cmd: |
+      [[ -f package-lock.json ]] && sha1sum package-lock.json | cut -d' ' -f1
+    cmd: docker build -t myrepo/app:${LETS_CHECKSUM} .
+```
 
 ### `persist_checksum`
 
@@ -852,7 +867,7 @@ commands:
 
 This feature is useful when you want to know that something has changed between two executions of a command.
 
-`persist_checksum` can be used only if `checksum` declared for command.
+`persist_checksum` can be used only if `checksum` or `checksum_cmd` declared for command.
 
 If set to `true`, each run all calculated checksums will be stored to disk.
 
@@ -877,6 +892,19 @@ commands:
         - Readme.md
 ```
 
+`checksum_cmd` can be persisted too:
+
+```yaml
+commands:
+  build-image:
+    persist_checksum: true
+    checksum_cmd: git rev-parse HEAD
+    cmd: |
+      if [[ ${LETS_CHECKSUM_CHANGED} == true ]]; then
+        docker build -t myrepo/app:${LETS_CHECKSUM} .
+      fi
+```
+
 Resulting env will be:
 
 * `LETS_CHECKSUM_DEPS` - checksum of deps files
@@ -937,64 +965,3 @@ commands:
 
 `args` is used only with [ref](#ref) and allows to set additional positional args to referenced command. See [ref](#ref) example.
 
-
-### `group`
-
-`key: group`
-
-`type: string`
-
-Commands can be organized into groups for better readability in the help output. To assign a command to a group, use the `group` key:
-
-```yaml
-commands:
-  build:
-    group: Build & Deploy
-    description: Build the project
-    cmd: npm run build
-
-  deploy:
-    group: Build & Deploy
-    description: Deploy the project
-    cmd: npm run deploy
-
-  test:
-    group: Testing
-    description: Run tests
-    cmd: npm test
-```
-
-When you run `lets help`, commands will be listed under their respective groups, making it easier to find related commands.
-
-```
-Commands:
-
-  Build & Deploy
-    build       Build the project
-    deploy      Deploy the project
-
-  Testing
-    test        Run tests
-```
-
-
-## Aliasing:
-
-Lets supports YAML aliasing in various places in the config
-
-### Env aliasing
-
-You can define any mapping and alias it in `env` configuration:
-
-```yaml
-shell: bash
-
-.default-env: &default-env
-  FOO: BAR
-
-env:
-  <<: *default-env
-  HELLO: WORLD
-```
-
-This will merge `env` and `.default-env`. Any environment variables declarations after `<<: ` will override variables defined in aliased map.

internal/checksum/checksum.go

@@ -6,8 +6,10 @@ import (
 	"encoding/hex"
 	"fmt"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"sort"
+	"strings"
 
 	"github.com/lets-cli/lets/internal/set"
 	"github.com/lets-cli/lets/internal/util"
@@ -103,6 +105,19 @@ func getChecksumsKeys(mapping map[string][]string) []string {
 	return keys
 }
 
+func CalculateChecksumFromCmd(shell string, workDir string, script string) (string, error) {
+	cmd := exec.Command(shell, "-c", script)
+	cmd.Dir = workDir
+
+	out, err := cmd.Output()
+	if err != nil {
+		return "", fmt.Errorf("can not calculate checksum from cmd: %s: %w", script, err)
+	}
+
+	res := string(out)
+	return strings.TrimSpace(res), nil
+}
+
 // CalculateChecksumFromSources calculates checksum from checksumSources.
 func CalculateChecksumFromSources(workDir string, checksumSources map[string][]string) (map[string]string, error) {
 	checksumMap := make(map[string]string)

internal/checksum/checksum_test.go

@@ -3,6 +3,7 @@ package checksum
 import (
 	"fmt"
 	"os"
+	"path/filepath"
 	"testing"
 
 	"github.com/lets-cli/lets/internal/test"
@@ -136,3 +137,21 @@ func TestCalculateChecksumFromListOrMap(t *testing.T) {
 		)
 	}
 }
+
+func TestCalculateChecksumFromCmdUsesWorkDir(t *testing.T) {
+	tempDir := t.TempDir()
+	checksumFilePath := filepath.Join(tempDir, "checksum.txt")
+
+	if err := os.WriteFile(checksumFilePath, []byte("checksum-from-workdir"), 0o600); err != nil {
+		t.Fatalf("can not write checksum file. Error: %s", err)
+	}
+
+	checksumResult, err := CalculateChecksumFromCmd("sh", tempDir, "cat checksum.txt")
+	if err != nil {
+		t.Fatalf("checksum command failed. Error: %s", err)
+	}
+
+	if checksumResult != "checksum-from-workdir" {
+		t.Fatalf("wrong checksum output. Expect: %s, got: %s", "checksum-from-workdir", checksumResult)
+	}
+}

internal/config/config/command.go

@@ -36,6 +36,7 @@ type Command struct {
 	Depends         *Deps
 	ChecksumMap     map[string]string
 	PersistChecksum bool
+	ChecksumCmd     string
 	// args from 'lets run --debug' will become [--debug]
 	Args []string
 
@@ -73,7 +74,8 @@ func (c *Command) UnmarshalYAML(unmarshal func(any) error) error {
 		After           string
 		Ref             string
 		Checksum        *Checksum
-		PersistChecksum bool `yaml:"persist_checksum"`
+		ChecksumCmd     string `yaml:"checksum_cmd"`
+		PersistChecksum bool   `yaml:"persist_checksum"`
 	}
 
 	if err := unmarshal(&cmd); err != nil {
@@ -120,9 +122,13 @@ func (c *Command) UnmarshalYAML(unmarshal func(any) error) error {
 		c.ChecksumSources = *cmd.Checksum
 	}
 
+	if cmd.ChecksumCmd != "" {
+		c.ChecksumCmd = cmd.ChecksumCmd
+	}
+
 	c.PersistChecksum = cmd.PersistChecksum
-	if len(c.ChecksumSources) == 0 && c.PersistChecksum {
-		return errors.New("'persist_checksum' must be used with 'checksum'")
+	if len(c.ChecksumSources) == 0 && c.ChecksumCmd == "" && c.PersistChecksum {
+		return errors.New("'persist_checksum' must be used with 'checksum' or 'checksum_cmd'")
 	}
 
 	if cmd.Ref != "" {
@@ -189,6 +195,7 @@ func (c *Command) Clone() *Command {
 		Depends:            c.Depends.Clone(),
 		ChecksumMap:        cloneMap(c.ChecksumMap),
 		PersistChecksum:    c.PersistChecksum,
+		ChecksumCmd:        c.ChecksumCmd,
 		ChecksumSources:    cloneMapSlice(c.ChecksumSources),
 		persistedChecksums: cloneMap(c.persistedChecksums),
 		Args:               cloneSlice(c.Args),
@@ -227,7 +234,17 @@ func (c *Command) Help() string {
 	return strings.TrimSuffix(buf.String(), "\n")
 }
 
-func (c *Command) ChecksumCalculator(workDir string) error {
+func (c *Command) ChecksumCalculator(shell, workDir string) error {
+	if c.ChecksumCmd != "" {
+		checksumResult, err := checksum.CalculateChecksumFromCmd(shell, workDir, c.ChecksumCmd)
+		if err != nil {
+			return err
+		}
+		c.ChecksumMap = make(map[string]string, 1)
+		c.ChecksumMap[checksum.DefaultChecksumKey] = checksumResult
+		return nil
+	}
+
 	if len(c.ChecksumSources) == 0 {
 		return nil
 	}