tests: templ generate exits with 0 when there are errors

[jraby]

This is very similar to #278, when running templ generate on an invalid template, the command exits with 0:

Given the following templ file:

package main

templ hello(name string) {
        <div>Hello, { name }</div>
    <div
    ></div
}

Running generate yields this:

$ templ version
v0.2.543
$ templ generate; echo $?
Processing path: /home/jean/tmp/templ-exit-code
Generating production code: /home/jean/tmp/templ-exit-code
(✗) Error processing path: /home/jean/tmp/templ-exit-code/components.templ parsing error: <div>: expected end tag not present or invalid tag contents: line 5, col 5
(✗) Generated code for 1 templates with 1 errors in 333.805µs
0

There seem to be an issue in the generateProduction method, where the errors are seen and counted, but not returned:

func generateProduction(ctx context.Context, w io.Writer, args Arguments, opts []generator.GenerateOpt, p *proxy.Handler) error {
    fmt.Fprintln(w, "Generating production code:", args.Path)
    start := time.Now()

    changesFound, errs := processChanges(
        ctx, w, nil, nil,
        args.Path, args.GenerateSourceMapVisualisations,
        opts, args.WorkerCount, false, args.KeepOrphanedFiles)
    if len(errs) > 0 {
        if errors.Is(errs[0], context.Canceled) {
            return errs[0]
        }
        logError(w, "Error processing path: %v\n", errors.Join(errs...))
    }

    if changesFound > 0 {
        if len(errs) > 0 {   <<<<<< should return something with errs
            logError(w, "Generated code for %d templates with %d errors in %s\n", changesFound, len(errs), time.Since(start))
        } else {
            logSuccess(w, "Generated code for %d templates with %d errors in %s\n", changesFound, len(errs), time.Since(start))
        }
        if args.Command != "" {
            fmt.Fprintf(w, "Executing command: %s\n", args.Command)
            if _, err := run.Run(ctx, args.Path, args.Command); err != nil {
                fmt.Fprintf(w, "Error starting command: %v\n", err)
            }
        }
    }

    return nil   <<<  errs are lost :(
}

[a-h]

Thanks for the report.

However, since the release you're using, that code has been completely rewritten from scratch, so the generateProduction function no longer exists in the codebase. The changes were made in #470 which adds a new fsnotify based watcher for --watch mode.

If you'd like to try the same operation with the latest CLI, by installing from source, e.g. go install github.com/a-h/templ/cmd/templ@8a1cd80d2e3880e55b6ae15e8245f8fec4e9b6cb, that would be great.

[jraby]

Hi, here's the result when using 8a1cd80:

$ ~/go/bin/templ generate
(!) templ version check: generator v0.2.562 is newer than templ version v0.2.543 found in go.mod file, consider running `go get -u github.com/a-h/templ` to upgrade
(✗) Error generating code [ file=/home/jean/tmp/templ-exit-code/test.templ error=/home/jean/tmp/templ-exit-code/test.templ parsing error: <div>: expected end tag not present or invalid tag contents: line 5, col 5 ]
(✗) Event handler failed [ error=failed to generate code for "/home/jean/tmp/templ-exit-code/test.templ": /home/jean/tmp/templ-exit-code/test.templ parsing error: <div>: expected end tag not present or invalid tag contents: line 5, col 5 ]
panic: send on closed channel

goroutine 12 [running]:
github.com/a-h/templ/cmd/templ/generatecmd.Generate.Run.func3.1({{0xc00002e420?, 0xc00005e788?}, 0x5e798?})
        /home/jean/go/pkg/mod/github.com/a-h/[email protected]/cmd/templ/generatecmd/cmd.go:173 +0x325
created by github.com/a-h/templ/cmd/templ/generatecmd.Generate.Run.func3 in goroutine 10
        /home/jean/go/pkg/mod/github.com/a-h/[email protected]/cmd/templ/generatecmd/cmd.go:166 +0x148

It definitely exits with a non zero code!

[a-h]

Ha, yes, very much a fail. It looks like the errors channel is being closed too early (only in the case that the --watch flag is set).

I'm able to reproduce it:

0 2 /Users/adrian/testt/onclick % templ generate -v
(!) templ version check: generator v0.2.566 is newer than templ version v0.2.513 found in go.mod file, consider running `go get -u github.com/a-h/templ` to upgrade
(✓) Starting post-generation handler
(✓) Walking directory [ path=/Users/adrian/testt/onclick devMode=false ]
(✓) Starting event handler
(✓) Processing file [ file=/Users/adrian/testt/onclick/components/template_templ.go ]
(✓) Processing file [ file=/Users/adrian/testt/onclick/components/template.templ ]
(✓) Dev mode not enabled, process can finish early
(✓) Waiting for push handler to complete
(✓) Waiting for event handler to complete
(✗) Error generating code [ file=/Users/adrian/testt/onclick/components/template.templ error=/Users/adrian/testt/onclick/components/template.templ parsing error: <div>: expected end tag not present or invalid tag contents: line 8, col 5 ]
(✗) Event handler failed [ error=failed to generate code for "/Users/adrian/testt/onclick/components/template.templ": /Users/adrian/testt/onclick/components/template.templ parsing error: <div>: expected end tag not present or invalid tag contents: line 8, col 5 ]
panic: send on closed channel

goroutine 7 [running]:
github.com/a-h/templ/cmd/templ/generatecmd.Generate.Run.func3.1({{0x1400002e3c0?, 0x14000059670?}, 0x59680?})
        /Users/adrian/github.com/a-h/templ/cmd/templ/generatecmd/cmd.go:173 +0x240
created by github.com/a-h/templ/cmd/templ/generatecmd.Generate.Run.func3 in goroutine 21
        /Users/adrian/github.com/a-h/templ/cmd/templ/generatecmd/cmd.go:166 +0x108

[a-h]

I've taken a look at this area and made a few improvements. For example, I noticed that the logging showed you errors, but didn't show you if the error was cleared (by editing the file). So even though there weren't any more errors, the terminal output didn't show you that.

If you could give e78dbc1 a try out, that would be excellent.

[jraby]

Looks like it is working now!

I'm not familiar with the codebase, but do you think it would warrant a test for that behavior? (exit != 0 on error?)

[a-h]

Yeah, it would be worth a test. There's only a test on the happy path (successful generation) at the moment.