@spec best_shared_version(String.t(), map()) :: {:ok, String.t()} | :no_common_version

Finds the best version of a package that satisfies all dependents.

Given a package name and a lockfile, looks at all packages that depend on it and finds a version (if any) that satisfies all their ranges.

@spec count(map()) :: non_neg_integer()

Counts package groups installed at multiple versions.

@spec find(map()) :: [%{name: String.t(), versions: [String.t()]}]

Finds packages installed at multiple versions.

Returns maps with the base package name and sorted distinct versions.

@spec find_duplicates(map()) :: [{String.t(), [String.t()]}]

Finds packages in the lockfile that could potentially be deduped.

Returns a list of {name, versions} where versions is a list of version strings for packages that appear in multiple forms.

@spec format_report([%{name: String.t(), versions: [String.t()]}]) :: String.t()

Formats duplicate report for display.

@spec potential_savings([%{name: String.t(), versions: [String.t()]}]) ::
  non_neg_integer()

Returns the number of extra package versions that dedupe could remove.

@spec savings_estimate(map()) :: %{
  packages: non_neg_integer(),
  duplicates: non_neg_integer()
}

Calculates how many bytes could be saved by deduplication.

This is an estimate based on the number of duplicate package entries.

@spec summary(map()) :: %{
  total_packages: non_neg_integer(),
  unique_packages: non_neg_integer(),
  duplicate_groups: non_neg_integer(),
  saveable: non_neg_integer()
}

Returns a summary of the deduplication analysis.