feat: AllowEmpty option to keep empty env values instead of defaults#421
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c-tonneslan wants to merge 2 commits into
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feat: AllowEmpty option to keep empty env values instead of defaults#421c-tonneslan wants to merge 2 commits into
c-tonneslan wants to merge 2 commits into
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…sOnly SetDefaultsForZeroValuesOnly is about defaults: an env var that's actually set should still take precedence over an already-populated struct field. The previous check treated any non-empty value the same way, so an explicit override via the environment was silently dropped the moment the destination field was non-zero. Plumb the isDefault flag (which getOr already computes) out of get() and only skip setting when the value came from a default. Real env values keep flowing through. Fixes caarlos0#364. Signed-off-by: Charlie Tonneslan <cst0520@gmail.com>
Today an explicitly-set-but-empty env variable falls back to envDefault. That's useful for the common shell mistake of leaving an unset variable as "", but it also means callers can't ever clear out a string via the environment. Add an AllowEmpty option that disables the empty-falls-back-to-default hop. Default behaviour is unchanged. Closes caarlos0#406 Signed-off-by: Charlie Tonneslan <cst0520@gmail.com>
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Closes #406.
Today an explicitly-set-but-empty env variable falls back to envDefault. That's useful for the common shell mistake of leaving an unset variable as "", but it also means callers can't ever clear out a string via the environment.
Added an `AllowEmpty` option that disables the empty-falls-back-to-default hop:
```go
env.ParseWithOptions(&cfg, env.Options{
Environment: map[string]string{"STR": ""},
AllowEmpty: true,
})
```
With `AllowEmpty: false` (the default) behaviour is unchanged, and the "env var is unset" path still falls back to the default in either mode. Test added that covers all three combinations.