Return the age of the index file in days (as a Double).

Reduced-verbosity version of getInstalledPackages

Get filename base (i.e. without file extension) for index-related files

Secure cabal repositories use a new extended & incremental 01-index.tar. In order to avoid issues resulting from clobbering new/old-style index data, we save them locally to different names.

Example: Use indexBaseName repo . "tar.gz" to compute the FilePath of the 00-index.tar.gz/01-index.tar.gz file.

A set of files (or directories) that can be monitored to detect when there might have been a change in the installed packages.

Read a repository index from disk, from the local files specified by a list of Repos.

All the SourcePackages are marked as having come from the appropriate Repo.

This is a higher level wrapper used internally in cabal-install.

A set of files (or directories) that can be monitored to detect when there might have been a change in the source packages.

Index state of multiple repositories

Variant of getSourcePackages which allows getting the source packages at a particular IndexState.

Current choices are either the latest (aka HEAD), or the index as it was at a particular time.

Returns also the total index where repositories' RepoIndexState's are not HEAD. This is used in v2-freeze.

Ordered list of active repositories.

Note, this does nothing if ActiveRepoRest is present.

Which index do we mean?

Specification of the state of a specific repo package index

An index entry is either a normal package, or a local build tree reference.

Read 00-index.tar.gz and extract .cabal and preferred-versions files

We read the index using read, which gives us a lazily constructed TarEntries. We translate it to a list of entries using tarEntriesList, which preserves the lazy nature of TarEntries, and finally concatMap a function over this to translate it to a list of IO actions returning PackageOrDeps. We can use lazySequence to turn this into a list of PackageOrDeps, still maintaining the lazy nature of the original tar read.

It is not necessary to call this, as the cache will be updated when the index is read normally. However you can do the work earlier if you like.

Write the IndexState to the filesystem

Read out the "current" index timestamp, i.e., what timestamp you would use to revert to this version.

Note: this is not the same as readIndexTimestamp! This resolves HEAD to the index's isiHeadTime, i.e. the index latest known timestamp.

Return NoTimestamp if the index has never been updated.

A build tree reference is either a link or a snapshot.

Expected name of the 'preferred-versions' file.

Contains special constraints, such as a preferred version of a package or deprecations of certain package versions.

Expected format:

binary > 0.9.0.0 || < 0.9.0.0
text == 1.2.1.0

Does the given filename match with the expected name of 'preferred-versions'?

Parse `preferred-versions` file, collecting parse errors that can be shown in error messages.

Parser error of the `preferred-versions` file.