Print suggestions upon failing to find a package by name

CHANGELOG.md

@@ -16,6 +16,7 @@ Other improvements:
 - Fixed empty output for `--verbose-stats` when there are no errors or warnings.
 - Added support for `--package-set` options for `spago upgrade`.
 - `spago repl` now writes a `.purs-repl` file, unless already there, containing `import Prelude`.
+- Added typo suggestions upon failing to find a package by name.
 
 ## [0.21.0] - 2023-05-04
 

spago.lock

@@ -419,6 +419,7 @@ workspace:
         - routing-duplex
         - spago-core
         - strings
+        - strings-extra
         - transformers
         - tuples
         - unfoldable
@@ -527,6 +528,7 @@ workspace:
         - st
         - string-parsers
         - strings
+        - strings-extra
         - stringutils
         - tailrec
         - these
@@ -674,6 +676,7 @@ workspace:
         - st
         - string-parsers
         - strings
+        - strings-extra
         - stringutils
         - tailrec
         - these
@@ -3006,6 +3009,17 @@ packages:
       - tuples
       - unfoldable
       - unsafe-coerce
+  strings-extra:
+    type: registry
+    version: 4.0.0
+    integrity: sha256-tah7VFvEvFF4tpWXgWwGFIynpWHkYe5tpy6bWi5tMpU=
+    dependencies:
+      - arrays
+      - foldable-traversable
+      - maybe
+      - prelude
+      - strings
+      - unicode
   stringutils:
     type: registry
     version: 0.0.12

spago.yaml

@@ -63,6 +63,7 @@ package:
     - routing-duplex
     - spago-core
     - strings
+    - strings-extra
     - transformers
     - tuples
     - unfoldable

src/Spago/Command/Fetch.purs

@@ -27,6 +27,7 @@ import Data.Int as Int
 import Data.Map as Map
 import Data.Newtype (wrap)
 import Data.Set as Set
+import Data.String (joinWith)
 import Data.Traversable (sequence)
 import Effect.Aff as Aff
 import Effect.Ref as Ref
@@ -532,8 +533,15 @@ getTransitiveDepsFromPackageSet packageSet deps = do
     printPackageError :: PackageName -> String
     printPackageError p = "  - " <> PackageName.print p <> "\n"
 
+    printNotInPackageSetError :: PackageName -> String
+    printNotInPackageSetError p = "  - " <> PackageName.print p <> strSuggestions
+      where
+        strSuggestions = case typoSuggestions PackageName.print p (Map.keys packageSet) of
+          [] -> "\n"
+          suggestions -> " (did you mean: " <> joinWith ", " (PackageName.print <$> suggestions) <> ")\n"
+
     init :: TransitiveDepsResult
-    init = { packages: (Map.empty :: Map PackageName Package), errors: mempty }
+    init = { packages: Map.empty, errors: mempty }
 
     go :: Set PackageName -> PackageName -> StateT TransitiveDepsResult (Spago (FetchEnv a)) Unit
     go seen dep = do
@@ -578,7 +586,7 @@ getTransitiveDepsFromPackageSet packageSet deps = do
   when (not (Set.isEmpty errors.cycle)) do
     die $ "The following packages have circular dependencies:\n" <> foldMap printPackageError (Set.toUnfoldable errors.cycle :: Array PackageName)
   when (not (Set.isEmpty errors.notInPackageSet)) do
-    die $ "The following packages do not exist in your package set:\n" <> foldMap printPackageError errors.notInPackageSet
+    die $ "The following packages do not exist in your package set:\n" <> foldMap printNotInPackageSetError errors.notInPackageSet
   when (not (Set.isEmpty errors.notInIndex)) do
     die $ "The following packages do not exist in the package index:\n" <> foldMap printPackageError errors.notInIndex
   pure packages

src/Spago/Config.purs

@@ -166,7 +166,7 @@ type ReadWorkspaceOptions =
 
 -- | Reads all the configurations in the tree and builds up the Map of local
 -- | packages to be integrated in the package set
-readWorkspace :: ReadWorkspaceOptions -> Spago (Registry.RegistryEnv _) Workspace
+readWorkspace :: ∀ a. ReadWorkspaceOptions -> Spago (Registry.RegistryEnv a) Workspace
 readWorkspace { maybeSelectedPackage, pureBuild, migrateConfig } = do
   logInfo "Reading Spago workspace configuration..."
 
@@ -272,9 +272,14 @@ readWorkspace { maybeSelectedPackage, pureBuild, migrateConfig } = do
       Nothing -> die
         $ [ toDoc $ "Selected package " <> PackageName.print name <> " was not found in the local packages." ]
         <> case (Array.fromFoldable $ Map.keys workspacePackages) of
-          [] -> [ toDoc "No available packages." ]
-          pkgs -> [ toDoc "Available packages:", indent (toDoc pkgs) ]
-      Just p -> pure (Just p)
+          [] ->
+            [ toDoc "No available packages." ]
+          pkgs ->
+            case typoSuggestions PackageName.print name pkgs of
+              [] -> [ toDoc "All available packages:", indent (toDoc pkgs) ]
+              suggestions -> [ toDoc "Did you mean:", indent (toDoc suggestions) ]
+      Just p ->
+        pure (Just p)
 
   logDebug "Reading the lockfile..."
   maybeLockfileContents <- FS.exists "spago.lock" >>= case _ of

src/Spago/Prelude.purs

@@ -1,21 +1,22 @@
 module Spago.Prelude
   ( HexString(..)
   , OnlineStatus(..)
+  , isPrefix
   , mkTemp
   , mkTemp'
   , module Spago.Core.Prelude
-  , parallelise
   , parTraverseSpago
+  , parallelise
   , parseLenientVersion
   , parseUrl
   , partitionEithers
   , shaToHex
+  , typoSuggestions
   , unsafeFromRight
   , unsafeLog
   , unsafeStringify
   , withBackoff'
   , withForwardSlashes
-  , isPrefix
   ) where
 
 import Spago.Core.Prelude
@@ -29,6 +30,7 @@ import Data.Int as Int
 import Data.Maybe as Maybe
 import Data.String (Pattern(..), Replacement(..))
 import Data.String as String
+import Data.String.Extra (levenshtein)
 import Data.Traversable (class Traversable)
 import Effect.Aff as Aff
 import Effect.Now as Now
@@ -169,3 +171,18 @@ withForwardSlashes = String.replaceAll (Pattern "\\") (Replacement "/")
 isPrefix :: String.Pattern -> String -> Boolean
 isPrefix p = isJust <<< String.stripPrefix p
 
+typoSuggestions :: ∀ f a. Foldable.Foldable f => (a -> String) -> a -> f a -> Array a
+typoSuggestions toString typo allOptions =
+  allOptions
+    # foldl pickClosestOnes []
+    # Array.sortWith snd
+    # Array.take 5
+    <#> fst
+  where
+    pickClosestOnes acc item =
+      let distance = levenshtein (toString typo) (toString item)
+      in
+        if distance <= 2 then
+          (item /\ distance) `Array.cons` acc
+        else
+          acc

test-fixtures/missing-dependencies.txt

@@ -4,5 +4,7 @@ Reading Spago workspace configuration...
 
 
 ❌ The following packages do not exist in your package set:
-  - bar
-  - foo
+  - arrys (did you mean: arrays)
+  - bar-bar-bar
+  - effcet (did you mean: effect)
+  - foo-foo-foo

test-fixtures/package-typo-suggestions/1.txt

@@ -0,0 +1,6 @@
+Reading Spago workspace configuration...
+
+❌ Selected package inder was not found in the local packages.
+Did you mean:
+  finder
+  binder

test-fixtures/package-typo-suggestions/2.txt

@@ -0,0 +1,5 @@
+Reading Spago workspace configuration...
+
+❌ Selected package flounder was not found in the local packages.
+Did you mean:
+  founder

test-fixtures/package-typo-suggestions/3.txt

@@ -0,0 +1,8 @@
+Reading Spago workspace configuration...
+
+❌ Selected package totally-bogus was not found in the local packages.
+All available packages:
+  binder
+  finder
+  founder
+  root

test/Spago/Errors.purs

@@ -3,10 +3,13 @@ module Test.Spago.Errors where
 import Test.Prelude
 
 import Data.Array as Array
+import Data.Foldable (traverse_)
+import Data.String (joinWith)
 import Data.String as String
 import Spago.FS as FS
 import Test.Spec (Spec)
 import Test.Spec as Spec
+import Test.Spec.Assertions.String (shouldContain)
 
 spec :: Spec Unit
 spec = Spec.around withTempDir do
@@ -20,3 +23,15 @@ spec = Spec.around withTempDir do
     Spec.it "fails for package names that are too long" \{ spago, fixture } -> do
       let name = String.joinWith "" $ Array.replicate 256 "a"
       spago [ "init", "--name", name ] >>= shouldBeFailureErr (fixture "package-name-too-long-stderr.txt")
+
+    Spec.it "prints suggested package names when package is not found" \{ spago, fixture } -> do
+      spago [ "init", "--name", "root" ] >>= shouldBeSuccess
+
+      ["finder", "binder", "founder"] # traverse_ \name -> do
+        FS.mkdirp name
+        FS.writeTextFile (name <> "/spago.yaml") $
+          "{ package: { name: \"" <> name <> "\", dependencies: [] } }"
+
+      spago [ "build", "-p", "inder" ] >>= shouldBeFailureErr (fixture "package-typo-suggestions/1.txt")
+      spago [ "build", "-p", "flounder" ] >>= shouldBeFailureErr (fixture "package-typo-suggestions/2.txt")
+      spago [ "build", "-p", "totally-bogus" ] >>= shouldBeFailureErr (fixture "package-typo-suggestions/3.txt")

test/Spago/Install.purs

@@ -59,7 +59,7 @@ spec = Spec.around withTempDir do
 
     Spec.it "can't add dependencies that are not in the package set" \{ spago, fixture } -> do
       spago [ "init", "--name", "aaaa", "--package-set", "29.3.0" ] >>= shouldBeSuccess
-      spago [ "install", "foo", "bar" ] >>= shouldBeFailureErr (fixture "missing-dependencies.txt")
+      spago [ "install", "foo-foo-foo", "bar-bar-bar", "effcet", "arrys" ] >>= shouldBeFailureErr (fixture "missing-dependencies.txt")
       checkFixture "spago.yaml" (fixture "spago-install-failure.yaml")
 
     Spec.it "does not allow circular dependencies" \{ spago, fixture } -> do