37 lines
1.5 KiB
Markdown
37 lines
1.5 KiB
Markdown
# go-clone
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5 years earlier, [gohack](https://github.com/rogpeppe/gohack) was written for the same reasons
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this tool was written. gohack has a good justification for this kind of tool so here it is:
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## Gohack: mutable checkouts of Go module dependencies
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The new Go module system is awesome. It ensures repeatable, deterministic
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builds of Go code. External module code is cached locally in a read-only
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directory, which is great for reproducibility. But if you're used to the
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global mutable namespace that is `$GOPATH`, there's an obvious question:
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what if I'm hacking on my program and I *want* to change one of those
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external modules?
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You might want to put a sneaky `log.Printf` statement to find out how
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some internal data structure works, or perhaps try out a bug fix to see
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if it solves your latest problem. But since all those external modules
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are in read-only directories, it's hard to change them. And you really
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don't want to change them anyway, because that will break the integrity
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checking that the Go tool does when building.
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Luckily the modules system provides a way around this: you can add a
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`replace` statement to the `go.mod` file which substitutes the contents
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of a directory holding a module for the readonly cached copy. You can of
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course do this manually, but gohack aims to make this process pain-free.
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## Install go-glone
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go install go.wit.com/apps/go-clone@latest
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## go-glone itself
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This will make a work directory and download everything needs to compile
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go-clone.
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go-clone --work go.wit.com/apps/go-clone
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