Perform a soft reload of some project state when editing theme files (tailwindlabs#918)

* Perform a soft reload of some project state when editing theme files

* Format

---------

Co-authored-by: Kris Braun <kris.braun@gmail.com>

Author: thecrypticace

packages/tailwindcss-language-server/src/projects.ts

@@ -108,6 +108,8 @@ export interface ProjectService {
   onCodeAction(params: CodeActionParams): Promise<CodeAction[]>
   onDocumentLinks(params: DocumentLinkParams): DocumentLink[]
   sortClassLists(classLists: string[]): string[]
+
+  reload(): Promise<void>
 }
 
 export enum DocumentSelectorPriority {
@@ -975,6 +977,42 @@ export async function createProjectService(
     enable() {
       enabled = true
     },
+
+    async reload() {
+      if (!state.v4) return
+
+      console.log('---- RELOADING DESIGN SYSTEM ----')
+      let css = await readCssFile(state.configPath)
+      let designSystem = await loadDesignSystem(
+        state.modules.tailwindcss.module,
+        state.configPath,
+        css,
+      )
+
+      // TODO: This is weird and should be changed
+      // We use Object.create so no global state is mutated until necessary
+      let pseudoState = Object.create(state, {
+        designSystem: {
+          value: designSystem,
+        },
+      })
+
+      let classList = designSystem.getClassList().map((className) => {
+        return [
+          className[0],
+          {
+            ...className[1],
+            color: getColor(pseudoState, className[0]),
+          },
+        ]
+      })
+
+      state.designSystem = designSystem
+      state.classList = classList as any
+
+      console.log('---- RELOADED ----')
+    },
+
     state,
     documentSelector() {
       return documentSelector

packages/tailwindcss-language-server/src/tw.ts

@@ -177,7 +177,7 @@ export class TW {
               isDefaultVersion: false,
             },
           }
-        },
+        }
       )
     } else {
       console.log("Searching for Tailwind CSS projects in the workspace's folders.")
@@ -224,9 +224,10 @@ export class TW {
     console.log(`[Global] Creating projects: ${JSON.stringify(workspaceDescription)}`)
 
     const onDidChangeWatchedFiles = async (
-      changes: Array<{ file: string; type: FileChangeType }>,
+      changes: Array<{ file: string; type: FileChangeType }>
     ): Promise<void> => {
       let needsRestart = false
+      let needsSoftRestart = false
 
       changeLoop: for (let change of changes) {
         let normalizedFilename = normalizePath(change.file)
@@ -242,12 +243,10 @@ export class TW {
           for (let [, project] of this.projects) {
             let twVersion = require('tailwindcss/package.json').version
             try {
-              let v = require(
-                resolveFrom(
-                  path.dirname(project.projectConfig.configPath),
-                  'tailwindcss/package.json',
-                ),
-              ).version
+              let v = require(resolveFrom(
+                path.dirname(project.projectConfig.configPath),
+                'tailwindcss/package.json'
+              )).version
               if (typeof v === 'string') {
                 twVersion = v
               }
@@ -259,6 +258,20 @@ export class TW {
           }
         }
 
+        for (let [, project] of this.projects) {
+          if (!project.state.v4) continue
+
+          let reloadableFiles = [
+            project.projectConfig.configPath,
+            ...project.projectConfig.config.entries.map((entry) => entry.path),
+          ]
+
+          if (!changeAffectsFile(normalizedFilename, reloadableFiles)) continue
+
+          needsSoftRestart = true
+          break changeLoop
+        }
+
         let isCssFile = minimatch(normalizedFilename, `**/${CSS_GLOB}`, {
           dot: true,
         })
@@ -300,6 +313,15 @@ export class TW {
         return
       }
 
+      if (needsSoftRestart) {
+        try {
+          await this.softRestart()
+        } catch {
+          this.restart()
+        }
+        return
+      }
+
       for (let [, project] of this.projects) {
         project.onFileEvents(changes)
       }
@@ -316,11 +338,11 @@ export class TW {
             .filter(
               (change, changeIndex, changes) =>
                 changes.findIndex((c) => c.file === change.file && c.type === change.type) ===
-                changeIndex,
+                changeIndex
             )
 
           await onDidChangeWatchedFiles(normalizedChanges)
-        }),
+        })
       )
 
       let disposable = await this.connection.client.register(
@@ -331,7 +353,7 @@ export class TW {
             { globPattern: `**/${PACKAGE_LOCK_GLOB}` },
             { globPattern: `**/${CSS_GLOB}` },
           ],
-        },
+        }
       )
 
       this.disposables.push(disposable)
@@ -360,14 +382,14 @@ export class TW {
         base,
         (err, events) => {
           onDidChangeWatchedFiles(
-            events.map((event) => ({ file: event.path, type: typeMap[event.type] })),
+            events.map((event) => ({ file: event.path, type: typeMap[event.type] }))
           )
         },
         {
           ignore: ignore.map((ignorePattern) =>
-            path.resolve(base, ignorePattern.replace(/^[*/]+/, '').replace(/[*/]+$/, '')),
+            path.resolve(base, ignorePattern.replace(/^[*/]+/, '').replace(/[*/]+$/, ''))
           ),
-        },
+        }
       )
 
       this.disposables.push({
@@ -388,7 +410,7 @@ export class TW {
             stabilityThreshold: 100,
             pollInterval: 20,
           },
-        },
+        }
       )
 
       await new Promise<void>((resolve) => {
@@ -399,17 +421,17 @@ export class TW {
         .on('add', (file) =>
           onDidChangeWatchedFiles([
             { file: path.resolve(base, file), type: FileChangeType.Created },
-          ]),
+          ])
         )
         .on('change', (file) =>
           onDidChangeWatchedFiles([
             { file: path.resolve(base, file), type: FileChangeType.Changed },
-          ]),
+          ])
         )
         .on('unlink', (file) =>
           onDidChangeWatchedFiles([
             { file: path.resolve(base, file), type: FileChangeType.Deleted },
-          ]),
+          ])
         )
 
       this.disposables.push({
@@ -433,9 +455,9 @@ export class TW {
           projectConfig,
           this.initializeParams,
           this.watchPatterns,
-          configTailwindVersionMap.get(projectConfig.configPath),
-        ),
-      ),
+          configTailwindVersionMap.get(projectConfig.configPath)
+        )
+      )
     )
 
     // init projects for documents that are _already_ open
@@ -465,19 +487,19 @@ export class TW {
         for (let [, project] of this.projects) {
           project.onUpdateSettings(settings)
         }
-      }),
+      })
     )
 
     this.disposables.push(
       this.connection.onShutdown(() => {
         this.dispose()
-      }),
+      })
     )
 
     this.disposables.push(
       this.documentService.onDidChangeContent((change) => {
         this.getProject(change.document)?.provideDiagnostics(change.document)
-      }),
+      })
     )
 
     this.disposables.push(
@@ -487,7 +509,7 @@ export class TW {
           project.enable()
           project.tryInit()
         }
-      }),
+      })
     )
   }
 
@@ -501,7 +523,7 @@ export class TW {
     projectConfig: ProjectConfig,
     params: InitializeParams,
     watchPatterns: (patterns: string[]) => void,
-    tailwindVersion: string,
+    tailwindVersion: string
   ): Promise<void> {
     let key = String(this.projectCounter++)
     const project = await createProjectService(
@@ -524,7 +546,7 @@ export class TW {
       () => this.refreshDiagnostics(),
       (patterns: string[]) => watchPatterns(patterns),
       tailwindVersion,
-      this.settingsCache.get,
+      this.settingsCache.get
     )
     this.projects.set(key, project)
 
@@ -571,11 +593,11 @@ export class TW {
 
   private onRequest(
     method: '@/tailwindCSS/sortSelection',
-    params: { uri: string; classLists: string[] },
+    params: { uri: string; classLists: string[] }
   ): { error: string } | { classLists: string[] }
   private onRequest(
     method: '@/tailwindCSS/getProject',
-    params: { uri: string },
+    params: { uri: string }
   ): { version: string } | null
   private onRequest(method: string, params: any): any {
     if (method === '@/tailwindCSS/sortSelection') {
@@ -776,6 +798,18 @@ export class TW {
     this.initPromise = undefined
     this.init()
   }
+
+  async softRestart(): Promise<void> {
+    // Tell each v4 project to reload it's design system
+    for (let [, project] of this.projects) {
+      if (!project.state.v4) continue
+
+      // "soft"-reload the project
+      try {
+        await project.reload()
+      } catch {}
+    }
+  }
 }
 
 function supportsDynamicRegistration(params: InitializeParams): boolean {