bazel__book/p18_20/cli.md

Bazel CLI

Build

Will generate entries in bazel-bin, bazel-out, bazel-<module> and bazel-testlogs.

In the p18_20 example: the good_read.txt is generated in bazel-bin: it mirrors how a compilation chain would create a binary, not how to run it.

Mod

Interacts with the module dependency resolver.

• bazel mod tidy: like go mod tidy
• bazel mod explain: like go mod why
  • --verbose_explanations mode details for --explain

bazel mod explain gazelle
<root> (modern_build_systems@1.0)
├───gazelle@0.40.0 #
├───rules_go@0.51.0-rc2       In MODULE.bazel
│   └───gazelle@0.40.0 #      In MODULE.bazel
└───rules_jvm_external@6.10
    └───rules_android@0.6.6
        └───gazelle@0.40.0 #

Query

List targets. Like in Go, "..." means "everything". Example:

bazel query //...
Starting local Bazel server (9.0.0) and connecting to it...
//sandbox_demo:bad_read
//sandbox_demo:good_read

Run

Executes a generated binary. For the p18_20 example, it does not work because there is nothing to run.

Test

It's just a special case of bazel run:

• runs tests in sandbox,
• captures the output to logs,
• enforces timeouts,
• runs tests in parallel.
• designed for reproducibility and CI
• caches results

Tests can also be run with bazel run:

• directly in the shell, not sandboxed
• has access to envvars
• streams output to terminal
• run non-paralle
• always re-runs
• interactive, can use stdin and debuggers