tree 160c9ae27bb78c290c7760e8e9a7e788271a168c
parent fb77e1d7374710c62cb1dd8cf137415949bf7d19
author Abhinav Gupta <abg@uber.com> 1572911696 -0800
committer GitHub <noreply@github.com> 1572911696 -0800
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README: Fix legacy import path instructions (#60)

In migrating to Go modules, we had to decide between the import paths
github.com/uber-go/atomic and go.uber.org/atomic. We chose the latter.

As a result of this, users of the legacy import path would get an error
message similar to the following:

    github.com/uber-go/atomic: github.com/uber-go/atomic@v1.5.0: parsing go.mod:
    module declares its path as: go.uber.org/atomic
            but was required as: github.com/uber-go/atomic

We suggested that users of the legacy import path add the following to
their go.mod.

    replace github.com/uber-go/atomic => go.uber.org/atomic v1.5.0

This is inaccurate and will result in the following error message:

    go.uber.org/atomic@v1.5.0 used for two different module paths
    (github.com/uber-go/atomic and go.uber.org/atomic)

This was not detected before because `go mod tidy` works fine with this
`replace` directive. It fails only when it gets to `go build`.

After digging into this more, per section 4.4 of the resolution section
of [How can I resolve "parsing go.mod: unexpected module path" (..)][1],
the correct method of resolving this is to downgrade the legacy import
path to a version prior to the use of Go modules.

  [1]: https://github.com/golang/go/wiki/Modules#how-can-i-resolve-parsing-gomod-unexpected-module-path-and-error-loading-module-requirements-errors-caused-by-a-mismatch-between-import-paths-vs-declared-module-identity

So the correct `replace` directive here would be,

    replace github.com/uber-go/atomic => github.com/uber-go/atomic v1.4.0

This fix was verified both, locally and by @atibhav21 who first ran into
this.