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+---
+stage: Verify
+group: Continuous Integration
+info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#designated-technical-writers
+type: reference
+---
+
+# GitLab CI/CD script syntax
+
+You can use special syntax in [`script`](README.md#script) sections to:
+
+- [Split long commands](#split-long-commands) into multiline commands.
+- [Use color codes](#add-color-codes-to-script-output) to make job logs easier to review.
+- [Create custom collapsible sections](../jobs/index.md#custom-collapsible-sections)
+  to simplify job log output.
+
+## Split long commands
+
+You can split long commands into multiline commands to improve readability with
+`|` (literal) and `>` (folded) [YAML multiline block scalar indicators](https://yaml-multiline.info/).
+
+CAUTION: **Warning:**
+If multiple commands are combined into one command string, only the last command's
+failure or success is reported.
+[Failures from earlier commands are ignored due to a bug](https://gitlab.com/gitlab-org/gitlab-runner/-/issues/25394).
+To work around this, run each command as a separate `script:` item, or add an `exit 1`
+command to each command string.
+
+You can use the `|` (literal) YAML multiline block scalar indicator to write
+commands over multiple lines in the `script` section of a job description.
+Each line is treated as a separate command.
+Only the first command is repeated in the job log, but additional
+commands are still executed:
+
+```yaml
+job:
+  script:
+    - |
+      echo "First command line."
+      echo "Second command line."
+      echo "Third command line."
+```
+
+The example above renders in the job log as:
+
+```shell
+$ echo First command line # collapsed multiline command
+First command line
+Second command line.
+Third command line.
+```
+
+The `>` (folded) YAML multiline block scalar indicator treats empty lines between
+sections as the start of a new command:
+
+```yaml
+job:
+  script:
+    - >
+      echo "First command line
+      is split over two lines."
+
+      echo "Second command line."
+```
+
+This behaves similarly to multiline commands without the `>` or `|` block
+scalar indicators:
+
+```yaml
+job:
+  script:
+    - echo "First command line
+      is split over two lines."
+
+      echo "Second command line."
+```
+
+Both examples above render in the job log as:
+
+```shell
+$ echo First command line is split over two lines. # collapsed multiline command
+First command line is split over two lines.
+Second command line.
+```
+
+When you omit the `>` or `|` block scalar indicators, GitLab concatenates non-empty
+lines to form the command. Make sure the lines can run when concatenated.
+
+[Shell here documents](https://en.wikipedia.org/wiki/Here_document) work with the
+`|` and `>` operators as well. The example below transliterates lower case letters
+to upper case:
+
+```yaml
+job:
+  script:
+    - |
+      tr a-z A-Z << END_TEXT
+        one two three
+        four five six
+      END_TEXT
+```
+
+Results in:
+
+```shell
+$ tr a-z A-Z << END_TEXT # collapsed multiline command
+  ONE TWO THREE
+  FOUR FIVE SIX
+```
+
+## Add color codes to script output
+
+Script output can be colored using [ANSI escape codes](https://en.wikipedia.org/wiki/ANSI_escape_code#Colors),
+or by running commands or programs that output ANSI escape codes.
+
+For example, using [Bash with color codes](https://misc.flogisoft.com/bash/tip_colors_and_formatting):
+
+```yaml
+job:
+  script:
+    - echo -e "\e[31mThis text is red,\e[0m but this text isn't\e[31m however this text is red again."
+```
+
+You can define the color codes in Shell variables, or even [custom environment variables](../variables/README.md#custom-environment-variables),
+which makes the commands easier to read and reusable.
+
+For example, using the same example as above and variables defined in a `before_script`:
+
+```yaml
+job:
+  before_script:
+    - TXT_RED="\e[31m" && TXT_CLEAR="\e[0m"
+  script:
+    - echo -e "${TXT_RED}This text is red,${TXT_CLEAR} but this part isn't${TXT_RED} however this part is again."
+    - echo "This text is not colored"
+```
+
+Or with [PowerShell color codes](https://superuser.com/a/1259916):
+
+```yaml
+job:
+  before_script:
+    - $esc="$([char]27)"; $TXT_RED="$esc[31m"; $TXT_CLEAR="$esc[0m"
+  script:
+    - Write-Host $TXT_RED"This text is red,"$TXT_CLEAR" but this text isn't"$TXT_RED" however this text is red again."
+    - Write-Host "This text is not colored"
+```