What causes "GITHUB_PR_COMMIT_HASH is not set! This must be run from within CI" in linera-io/linera-protocol?

Run inside a pull_request-triggered workflow that exports GITHUB_PR_COMMIT_HASH (typically from github.event.pull_request.head.sha)

linera-io/linera-protocol · error

GITHUB_PR_COMMIT_HASH is not set! This must be run from with

Error message

GITHUB_PR_COMMIT_HASH is not set! This must be run from within CI

What it means

In CI mode, from_env reads GITHUB_PR_COMMIT_HASH — the head commit of the pull request — and fails when it is unset, because later steps compare runs and jobs against that exact commit. It is normally provided by the workflow config on pull_request events.

Source

Thrown at linera-summary/src/github.rs:124

        let env_pr_branch = env::var("GITHUB_PR_BRANCH");
        let env_base_branch = env::var("GITHUB_BASE_BRANCH");
        let env_pr_number = env::var("GITHUB_PR_NUMBER");

        let (pr_commit_hash, pr_branch, base_branch, pr_number) = if is_local {
            let (commit_hash, branch_name, base) = Self::get_local_git_info()?;
            (
                commit_hash,
                branch_name,
                base,
                pr_number.ok_or_else(|| anyhow!("pr_number is None"))?,
            )
        } else {
            let pr_string = env_pr_number.map_err(|_| {
                anyhow!("GITHUB_PR_NUMBER is not set! This must be run from within CI")
            })?;
            (
                env_pr_commit_hash.map_err(|_| {
                    anyhow!("GITHUB_PR_COMMIT_HASH is not set! This must be run from within CI")
                })?,
                env_pr_branch.map_err(|_| {
                    anyhow!("GITHUB_PR_BRANCH is not set! This must be run from within CI")
                })?,
                env_base_branch.map_err(|_| {
                    anyhow!("GITHUB_BASE_BRANCH is not set! This must be run from within CI")
                })?,
                pr_string
                    .parse()
                    .map_err(|_| anyhow!("GITHUB_PR_NUMBER is not a valid number: {pr_string}"))?,
            )
        };

        Ok(Self {
            repository: GithubRepository::from_env(is_local)?,
            pr_commit_hash,
            pr_branch,
            base_branch,

View on GitHub (pinned to 6c226ddcb3)

Solutions

Run inside a pull_request-triggered workflow that exports GITHUB_PR_COMMIT_HASH (typically from github.event.pull_request.head.sha)
Or export it manually: GITHUB_PR_COMMIT_HASH=<full-sha> alongside the other GITHUB_PR_* variables
Check the workflow's env: block — a typo'd variable name produces exactly this failure

Example fix

# before
env:
  GITHUB_PR_COMMIT: ${{ github.event.pull_request.head.sha }}
# after
env:
  GITHUB_PR_COMMIT_HASH: ${{ github.event.pull_request.head.sha }}

Defensive patterns

Strategy: validation

Validate before calling

#!/usr/bin/env bash
: "${GITHUB_PR_COMMIT_HASH:?GITHUB_PR_COMMIT_HASH is required (PR head sha)}"

Try / catch

if let Err(e) = Github::new(false, None) {
    if e.to_string().contains("GITHUB_PR_COMMIT_HASH") {
        eprintln!("export GITHUB_PR_COMMIT_HASH=${{ github.event.pull_request.head.sha }} in the workflow env");
    }
    return Err(e.into());
}

Prevention

Centralize the four GITHUB_PR_*/BASE exports in one reusable env block
Name variables exactly as the tool expects — no abbreviations
Add a workflow lint that greps for all required GITHUB_* names

When it happens

Trigger: A CI invocation missing GITHUB_PR_COMMIT_HASH: running outside GitHub Actions, or a workflow that forgot to export github.event.pull_request.head.sha into this variable.

Common situations: Custom workflow YAML that sets only some GITHUB_* variables; local emulation of CI; refactoring that renamed the export step.

Understand the failure class

Background: "environment variable is not set" and "Missing keys in environment" errors: what missing required env var messages mean and how to fix them — this error's family across 28 libraries.

Related errors

AI-assisted analysis of linera-io/linera-protocol@6c226ddcb3 (2026-08-22). Data as JSON: /api/errors/8db7d5970b70eea0. Report an issue: GitHub.