Suggest alternatives when active recipes are not found (#4169)

Author: timtebeek

rewrite-core/src/main/java/org/openrewrite/config/Environment.java

@@ -15,6 +15,7 @@
  */
 package org.openrewrite.config;
 
+import org.apache.commons.lang3.StringUtils;
 import org.openrewrite.Contributor;
 import org.openrewrite.Recipe;
 import org.openrewrite.RecipeException;
@@ -28,7 +29,10 @@
 import java.util.*;
 
 import static java.util.Collections.emptyList;
+import static java.util.Comparator.comparingInt;
+import static java.util.function.Function.identity;
 import static java.util.stream.Collectors.toList;
+import static java.util.stream.Collectors.toMap;
 
 public class Environment {
     private final Collection<? extends ResourceLoader> resourceLoaders;
@@ -134,24 +138,27 @@ public Collection<RecipeDescriptor> listRecipeDescriptors() {
     }
 
     public Recipe activateRecipes(Iterable<String> activeRecipes) {
-        List<Recipe> allRecipes = listRecipes();
+        Map<String, Recipe> recipesByName = listRecipes().stream().collect(toMap(Recipe::getName, identity()));
         List<String> recipesNotFound = new ArrayList<>();
         List<Recipe> activatedRecipes = new ArrayList<>();
         for (String activeRecipe : activeRecipes) {
-            boolean foundRecipe = false;
-            for (Recipe recipe : allRecipes) {
-                if (activeRecipe.equals(recipe.getName())) {
-                    activatedRecipes.add(recipe);
-                    foundRecipe = true;
-                    break;
-                }
-            }
-            if (!foundRecipe) {
+            Recipe recipe = recipesByName.get(activeRecipe);
+            if (recipe == null) {
                 recipesNotFound.add(activeRecipe);
+            } else {
+                activatedRecipes.add(recipe);
             }
         }
         if (!recipesNotFound.isEmpty()) {
-            throw new RecipeException("Recipes not found: " + String.join(", ", recipesNotFound));
+            List<String> suggestions = recipesNotFound.stream()
+                    .map(r -> recipesByName.keySet().stream()
+                            .min(comparingInt(a -> StringUtils.getLevenshteinDistance(a, r)))
+                            .orElse(r))
+                    .collect(toList());
+            String message = String.format("Recipes not found: %s\nDid you mean: %s",
+                    String.join(", ", recipesNotFound),
+                    String.join(", ", suggestions));
+            throw new RecipeException(message);
         }
         return new CompositeRecipe(activatedRecipes);
     }

rewrite-test/src/test/java/org/openrewrite/config/EnvironmentTest.java

@@ -30,6 +30,7 @@
 import java.util.Properties;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 import static org.openrewrite.test.SourceSpecs.text;
 
 class EnvironmentTest implements RewriteTest {
@@ -100,6 +101,41 @@ void listRecipes() {
         assertThat(changes).hasSize(1);
     }
 
+    @Test
+    void activeRecipeNotFoundSuggestions() {
+        var env = Environment.builder()
+          .load(
+            new YamlResourceLoader(
+              //language=yml
+              new ByteArrayInputStream(
+                """
+                  type: specs.openrewrite.org/v1beta/recipe
+                  name: test.ChangeTextToHello
+                  displayName: Change text to hello
+                  recipeList:
+                    - org.openrewrite.text.ChangeText:
+                        toText: Hello
+                  ---
+                  type: specs.openrewrite.org/v1beta/recipe
+                  name: test.ChangeTextToHelloWorld
+                  displayName: Change text to hello world
+                  recipeList:
+                    - org.openrewrite.text.ChangeText:
+                        toText: Hello
+                  """.getBytes()
+              ),
+              URI.create("rewrite.yml"),
+              new Properties()
+            )
+          )
+          .build();
+
+        assertThatExceptionOfType(RecipeException.class)
+          .isThrownBy(() -> env.activateRecipes("foo.ChangeTextToHelloWorld"))
+          .withMessageContaining("foo.ChangeTextToHelloWorld")
+          .withMessageContaining("test.ChangeTextToHelloWorld");
+    }
+
     @Test
     void recipeWithoutRequiredConfiguration() {
         var env = Environment.builder()