golang/go · error

invalid version interval: %q

Error message

invalid version interval: %q

What it means

Thrown by parseVersionInterval when an argument begins with '[' but does not end with ']'. The function expects a closed interval notation like '[v1.2.3,v1.4.5]'; a missing closing bracket makes the interval malformed and unparseable. This is used by `go mod edit` commands that accept version interval arguments (e.g., `-require`, `-exclude`, `-replace` with intervals).

Source

Thrown at src/cmd/go/internal/modcmd/edit.go:402

	if path != arg && !allowedVersionArg(version) {
		return path, version, fmt.Errorf("invalid %s version: %q", adj, version)
	}
	return path, version, nil
}

// parseVersionInterval parses a single version like "v1.2.3" or a closed
// interval like "[v1.2.3,v1.4.5]". Note that a single version has the same
// representation as an interval with equal upper and lower bounds: both
// Low and High are set.
func parseVersionInterval(arg string) (modfile.VersionInterval, error) {
	if !strings.HasPrefix(arg, "[") {
		if !allowedVersionArg(arg) {
			return modfile.VersionInterval{}, fmt.Errorf("invalid version: %q", arg)
		}
		return modfile.VersionInterval{Low: arg, High: arg}, nil
	}
	if !strings.HasSuffix(arg, "]") {
		return modfile.VersionInterval{}, fmt.Errorf("invalid version interval: %q", arg)
	}
	s := arg[1 : len(arg)-1]
	before, after, found := strings.Cut(s, ",")
	if !found {
		return modfile.VersionInterval{}, fmt.Errorf("invalid version interval: %q", arg)
	}
	low := strings.TrimSpace(before)
	high := strings.TrimSpace(after)
	if !allowedVersionArg(low) || !allowedVersionArg(high) {
		return modfile.VersionInterval{}, fmt.Errorf("invalid version interval: %q", arg)
	}
	return modfile.VersionInterval{Low: low, High: high}, nil
}

// allowedVersionArg returns whether a token may be used as a version in go.mod.
// We don't call modfile.CheckPathVersion, because that insists on versions
// being in semver form, but here we want to allow versions like "master" or
// "1234abcdef", which the go command will resolve the next time it runs (or

View on GitHub (pinned to b6b368adc5)

Solutions

1. Add the missing closing ']' to complete the interval: `[v1.2.3,v1.4.5` → `[v1.2.3,v1.4.5]`
2. If a single version is intended, drop the brackets entirely: `[v1.2.3]` → `v1.2.3`
3. Check shell quoting: ensure the brackets are inside single or double quotes to prevent shell interpretation

Example fix

// before
go mod edit -exclude=[v1.2.3,v1.4.5
// after
go mod edit -exclude=[v1.2.3,v1.4.5]

// Validate interval format before passing to go mod edit
func validateVersionInterval(arg string) error {
    if strings.HasPrefix(arg, "[") && !strings.HasSuffix(arg, "]") {
        return fmt.Errorf("interval must end with ]: %q", arg)
    }
    return nil
}

func isClosedInterval(s string) bool {
    return strings.HasPrefix(s, "[") && strings.HasSuffix(s, "]")
}

When it happens

Trigger: Calling `go mod edit` with a version interval argument that starts with '[' but lacks the closing ']', such as `-exclude=[v1.2.3,v1.4.5` or `-replace=old@v1.0.0=[v1.1.0`. Any argument matching `strings.HasPrefix(arg, "[")` but NOT `strings.HasSuffix(arg, "]")` hits this branch.

Common situations: Typo in shell quoting that strips the trailing bracket; copy-paste from documentation that truncated the example; shell glob or variable expansion that mangled the closing ']'; using a bracket notation when a single version was intended.

Related errors

• expecting a Go version like %q
• non-semver module version %q
• invalid version %q
• maximum supported Go version is %s
• non-canonical module version %q

AI-assisted analysis of golang/go@b6b368adc5 (2026-08-12). Data as JSON: /api/errors/1693bb44241f7303. Report an issue: GitHub.