Enable spago init and spago upgrade-set to use user-specified package-set tag rather than latest release (#680)

* Enable user to specify a tag when initializing project via --tag

* Add --tag option to `upgrade-set` command

* Only notify user that package set doesn't exist if Dhall gets a 404

* Move useLatestRelease to where clause in updatePackageSetVersion

* Inline shared code into updatePackageSetVersion

* Implement tests for `--tag` parameter

* Update changelog: add --tag as new feature and 'breaking changes'

* Update readme to document --tag argument

Author: JordanMartinez

CHANGELOG.md

@@ -7,6 +7,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+Breaking changes (😱!!!):
+- **Specify the package set version via `--tag` (#680)**
+
+  Example usage: `spago init --tag psc-0.13.2-20190725` and `spago upgrade-set --tag psc-0.13.2-20190725`. This is a breaking change because we are removing support for the old spacchetti/spacchetti-style location (i.e. in the src/packages.dhall) for the upgrade-set command.
+
 ## [0.16.0] - 2020-08-14
 
 Breaking changes (😱!!!):

README.md

@@ -233,7 +233,6 @@ you'll have to carefully:
 - try to run `spago install some-package` for packages in the set
 - [add the missing packages](#add-a-package-to-the-package-set) if not in the set
 
-
 ### See what commands and flags are supported
 
 For an overview of the available commands, run:
@@ -252,6 +251,14 @@ $ spago build --help
 This will give a detailed view of the command, and list any command-specific
 (vs global) flags.
 
+### Setup a new project using a specific package set
+
+Since `spago init` does not necessarily use the latest package set. Fortunately, you can specify which package set to use via the `--tag` argument. See the [`purescript/package-sets` repo's releases](https://github.com/purescript/package-sets/releases) for tags you can use:
+
+```bash
+$ spago init --tag "psc-0.13.8-20200822"
+```
+
 
 ### Install a direct dependency
 
@@ -557,23 +564,47 @@ if you could pull request it to the [Upstream package-set][package-sets] ❤️
 If you decide so, you can read up on how to do it [here][package-sets-contributing].
 
 
-### Automagically upgrade the package set
+### Upgrade the package set...
 
 The version of the package-set you depend on is fixed in the `packages.dhall` file
 (look for the `upstream` var).
 
 You can upgrade to the latest version of the package-set with the `upgrade-set`
-command, that will automatically find out the latest version, download it, and write
+command. It will download the package set and write
 the new url and hashes in the `packages.dhall` file for you.
 
+Spago can update the package set to the latest release or to a specific release automagically. If you wish to use a specific commit, you will have to manually edit one part of your `packages.dhall` file. Each is covered below.
+
+#### ...to the latest release automatically
+
 Running it would look something like this:
 
 ```bash
-$ spago upgrade-set
-Found the most recent tag for "purescript/package-sets": "psc-0.12.3-20190227"
-Package-set upgraded to latest tag "psc-0.12.3-20190227"
+$ spago  upgrade-set
+[info] Updating package-set tag to "psc-0.13.8-20200822"
+Fetching the new one and generating hashes.. (this might take some time)
+[info] Generating new hashes for the package set file so it will be cached.. (this might take some time)
+```
+
+#### ...to a specific release automatically
+
+If the package set exists, running `upgrade-set` would look something like this:
+
+```bash
+$ spago upgrade-set --tag "psc-0.13.8-20200822"
+[info] Updating package-set tag to "psc-0.13.8-20200822"
 Fetching the new one and generating hashes.. (this might take some time)
-Done. Updating the local package-set file..
+[info] Generating new hashes for the package set file so it will be cached.. (this might take some time)
+```
+
+If the package set does not exist, your `packages.dhall` file will not be touched and you will see a warning:
+
+```bash
+spago upgrade-set --tag "whoops-i-made-a-big-typo"
+[info] Updating package-set tag to "whoops-i-made-a-big-typo"
+Fetching the new one and generating hashes.. (this might take some time)
+[warn] Package-set tag "whoops-i-made-a-big-typo" in the repo "purescript/package-sets" does not exist.
+Will ignore user-specified tag and continue using current tag: "psc-0.13.4-20191025"
 ```
 
 If you wish to detach from tags for your package-set, you can of course point it to a
@@ -584,6 +615,15 @@ let upstream =
       https://raw.githubusercontent.com/purescript/package-sets/bd72269fec59950404a380a46e293bde34b4618f/src/packages.dhall
 ```
 
+#### ... to a specific tag manually
+
+If you wish to detach from tags for your package-set, you can of course point it to a
+specific commit. Just set your `upstream` to look something like this:
+
+```haskell
+let upstream =
+      https://raw.githubusercontent.com/purescript/package-sets/bd72269fec59950404a380a46e293bde34b4618f/src/packages.dhall
+```
 
 ### Monorepo
 

app/Spago.hs

@@ -45,11 +45,11 @@ main = withUtf8 $ do
         -> handleDefault shouldShowVersion
 
       -- ### Commands that need only a basic global env
-      Init force noComments
-        -> void $ Spago.Packages.initProject force noComments
-      PackageSetUpgrade
-        -> Spago.PackageSet.upgradePackageSet
-      Freeze 
+      Init force noComments tag
+        -> void $ Spago.Packages.initProject force noComments tag
+      PackageSetUpgrade tag
+        -> Spago.PackageSet.updatePackageSetVersion tag
+      Freeze
         -> Spago.PackageSet.freeze Spago.PackageSet.packagesPath
       Login 
         -> Spago.GitHub.login

package.yaml

@@ -93,6 +93,7 @@ library:
   - fsnotify
   - github
   - Glob
+  - http-types
   - http-client
   - http-conduit
   - lens-family-core

src/Spago/Build.hs

@@ -152,9 +152,9 @@ repl newPackages sourcePaths pursArgs depsOnly = do
       Temp.withTempDirectory cacheDir "spago-repl-tmp" $ \dir -> do
         Turtle.cd (Turtle.decodeString dir)
 
-        config@Config{ packageSet = PackageSet{..}, ..} 
-          <- Packages.initProject NoForce Dhall.WithComments
-        
+        config@Config{ packageSet = PackageSet{..}, ..}
+          <- Packages.initProject NoForce Dhall.WithComments Nothing
+
         let newConfig :: Config
             newConfig = config { Config.dependencies = dependencies <> newPackages }
         Run.withInstallEnv' (Just newConfig) (replAction purs)

src/Spago/CLI.hs

@@ -26,7 +26,7 @@ data Command
   = Default ShowVersion
 
   -- | Initialize a new project
-  | Init Force TemplateComments
+  | Init Force TemplateComments (Maybe Text)
 
   -- | Install (download) dependencies defined in spago.dhall
   | Install [PackageName]
@@ -47,7 +47,7 @@ data Command
   | Login
 
   -- | Upgrade the package-set to the latest release
-  | PackageSetUpgrade
+  | PackageSetUpgrade (Maybe Text)
 
   -- | Freeze the package-set so it will be cached
   | Freeze
@@ -148,6 +148,7 @@ parser = do
     usePsa       = bool UsePsa NoPsa <$> CLI.switch "no-psa" 'P' "Don't build with `psa`, but use `purs`"
     openDocs     = bool NoOpenDocs DoOpenDocs <$> CLI.switch "open" 'o' "Open generated documentation in browser (for HTML format only)"
     noComments   = bool WithComments NoComments <$> CLI.switch "no-comments" 'C' "Generate package.dhall and spago.dhall files without tutorial comments"
+    tag          = CLI.optional $ Opts.strOption (Opts.long "tag" <> Opts.help "Optional package set tag to be used instead of the latest one.")
     configPath   = CLI.optional $ CLI.optText "config" 'x' "Optional config path to be used instead of the default spago.dhall"
     chkModsUniq  = bool DoCheckModulesUnique NoCheckModulesUnique <$> CLI.switch "no-check-modules-unique" 'M' "Skip checking whether modules names are unique across all packages."
     transitive   = bool NoIncludeTransitive IncludeTransitive <$> CLI.switch "transitive" 't' "Include transitive dependencies"
@@ -180,7 +181,7 @@ parser = do
     initProject =
       ( "init"
       , "Initialize a new sample project, or migrate a psc-package one"
-      , Init <$> force <*> noComments
+      , Init <$> force <*> noComments <*> tag
       )
 
     build =
@@ -283,7 +284,7 @@ parser = do
     upgradeSet =
       ( "upgrade-set"
       , "Upgrade the upstream in packages.dhall to the latest package-sets release"
-      , pure PackageSetUpgrade
+      , PackageSetUpgrade <$> tag
       )
 
     freeze =

src/Spago/Dhall.hs

@@ -90,9 +90,11 @@ readRawExpr pathText = do
 
 writeRawExpr :: Text -> (Dhall.Header, DhallExpr Dhall.Import) -> IO ()
 writeRawExpr pathText (header, expr) = do
+  -- Verify that the package set exists
+  -- If Dhall gets a 404, it will throw a PrettyHttpException
+  resolvedExpr <- Dhall.Import.load expr
   -- After modifying the expression, we have to check if it still typechecks
   -- if it doesn't we don't write to file.
-  resolvedExpr <- Dhall.Import.load expr
   _ <- throws (Dhall.TypeCheck.typeOf resolvedExpr)
   writeTextFile pathText $ prettyWithHeader header expr
   format pathText

src/Spago/Messages.hs

@@ -140,12 +140,18 @@ failedToAddDeps pkgs = makeMessage $
   <> map ("- " <>) (NonEmpty.toList pkgs)
   <> [""]
 
-upgradingPackageSet :: Text -> Text
-upgradingPackageSet newTag = makeMessage
-  [ "Package-set upgraded to latest tag " <> surroundQuote newTag
+updatingPackageSet :: Text -> Text
+updatingPackageSet newTag = makeMessage
+  [ "Updating package-set tag to " <> surroundQuote newTag
   , "Fetching the new one and generating hashes.. (this might take some time)"
   ]
 
+nonExistentPackageSet :: Text -> Text -> Text -> Text -> Text
+nonExistentPackageSet org repo oldTag newTag = makeMessage
+  [ "Package-set tag " <> surroundQuote newTag <> " in the repo " <> surroundQuote (org <> "/" <> repo) <> " does not exist."
+  , "Will ignore user-specified tag and continue using current tag: " <> surroundQuote oldTag
+  ]
+
 freezePackageSet :: Text
 freezePackageSet = makeMessage
   [ "Generating new hashes for the package set file so it will be cached.. (this might take some time)"