feat(intention): add "Add explicit type" intention (#127)

Fixes #126

Author: i582

server/src/intentions/AddExplicitType.ts

@@ -0,0 +1,48 @@
+import {Intention, IntentionContext} from "@server/intentions/Intention"
+import {WorkspaceEdit} from "vscode-languageserver"
+import {File} from "@server/psi/File"
+import {asParserPoint} from "@server/utils/position"
+import {Position} from "vscode-languageclient"
+import {VarDeclaration} from "@server/psi/Node"
+import {FileDiff} from "@server/utils/FileDiff"
+
+export class AddExplicitType implements Intention {
+    id: string = "tact.add-explicit-type"
+    name: string = "Add explicit type"
+
+    findVariable(ctx: IntentionContext): VarDeclaration | null {
+        const referenceNode = nodeAtPosition(ctx.position, ctx.file)
+        if (referenceNode?.type !== "identifier") return null
+        const parent = referenceNode.parent
+        if (parent?.type !== "let_statement") return null
+        return new VarDeclaration(parent, ctx.file)
+    }
+
+    is_available(ctx: IntentionContext): boolean {
+        const variable = this.findVariable(ctx)
+        if (!variable) return false
+        return !variable.hasTypeHint()
+    }
+
+    invoke(ctx: IntentionContext): WorkspaceEdit | null {
+        const variable = this.findVariable(ctx)
+        if (!variable) return null
+        if (variable.hasTypeHint()) return null
+
+        const name = variable.nameIdentifier()
+        if (!name) return null
+
+        const inferredType = variable.value()?.type()
+        if (!inferredType) return null
+
+        const diff = FileDiff.forFile(ctx.file.uri)
+        diff.appendTo(name.endPosition.row, name.endPosition.column, `: ${inferredType.name()}`)
+
+        return diff.toWorkspaceEdit()
+    }
+}
+
+function nodeAtPosition(pos: Position, file: File) {
+    const cursorPosition = asParserPoint(pos)
+    return file.rootNode.descendantForPosition(cursorPosition)
+}

server/src/intentions/Intention.ts

@@ -0,0 +1,22 @@
+import {WorkspaceEdit} from "vscode-languageserver"
+import {File} from "@server/psi/File"
+import {Position} from "vscode-languageclient"
+
+export interface IntentionContext {
+    file: File
+    position: Position
+}
+
+export interface IntentionArguments {
+    fileUri: string
+    position: Position
+}
+
+export interface Intention {
+    id: string
+    name: string
+
+    is_available(ctx: IntentionContext): boolean
+
+    invoke(ctx: IntentionContext): WorkspaceEdit | null
+}

server/src/server.ts

@@ -80,6 +80,8 @@ import {TraitOrContractConstantsCompletionProvider} from "@server/completion/pro
 import {generateTlBTypeDoc} from "@server/documentation/tlb_type_documentation"
 import {BouncedTypeCompletionProvider} from "@server/completion/providers/BouncedTypeCompletionProvider"
 import {TopLevelCompletionProvider} from "@server/completion/providers/TopLevelCompletionProvider"
+import {Intention, IntentionArguments, IntentionContext} from "@server/intentions/Intention"
+import {AddExplicitType} from "@server/intentions/AddExplicitType"
 
 /**
  * Whenever LS is initialized.
@@ -1003,6 +1005,100 @@ connection.onInitialize(async (params: lsp.InitializeParams): Promise<lsp.Initia
         },
     )
 
+    const intentions: Intention[] = [new AddExplicitType()]
+
+    connection.onRequest(
+        lsp.ExecuteCommandRequest.type,
+        async (params: lsp.ExecuteCommandParams) => {
+            if (params.command === "tact/executeGetScopeProvider") {
+                const commandParams = params.arguments?.[0] as
+                    | lsp.TextDocumentPositionParams
+                    | undefined
+                if (!commandParams) return "Invalid parameters"
+
+                const file = PARSED_FILES_CACHE.get(commandParams.textDocument.uri)
+                if (!file) {
+                    return "File not found"
+                }
+
+                const node = nodeAtPosition(commandParams, file)
+                if (!node) {
+                    return "Node not found"
+                }
+
+                const referent = new Referent(node, file)
+                const scope = referent.useScope()
+                if (!scope) return "Scope not found"
+                if (scope instanceof LocalSearchScope) return scope.toString()
+                return "GlobalSearchScope"
+            }
+
+            if (!params.arguments || params.arguments.length === 0) return null
+
+            const intention = intentions.find(intention => intention.id === params.command)
+            if (!intention) return null
+
+            const args = params.arguments[0] as IntentionArguments
+
+            const file = findFile(args.fileUri)
+
+            const ctx: IntentionContext = {
+                file: file,
+                position: args.position,
+            }
+
+            const edits = intention.invoke(ctx)
+            if (!edits) return null
+
+            await connection.sendRequest(lsp.ApplyWorkspaceEditRequest.method, {
+                label: `Intention "${intention.name}"`,
+                edit: edits,
+            } as lsp.ApplyWorkspaceEditParams)
+
+            return null
+        },
+    )
+
+    connection.onRequest(
+        lsp.CodeActionRequest.type,
+        (params: lsp.CodeActionParams): lsp.CodeAction[] | null => {
+            const uri = params.textDocument.uri
+            if (uri.endsWith(".fif")) {
+                return null
+            }
+
+            const file = findFile(uri)
+
+            const ctx: IntentionContext = {
+                file: file,
+                position: params.range.start,
+            }
+
+            const actions: lsp.CodeAction[] = []
+
+            intentions.forEach(intention => {
+                if (!intention.is_available(ctx)) return
+
+                actions.push({
+                    title: intention.name,
+                    kind: lsp.CodeActionKind.QuickFix,
+                    command: {
+                        title: intention.name,
+                        command: intention.id,
+                        arguments: [
+                            {
+                                fileUri: file.uri,
+                                position: params.range.start,
+                            } as IntentionArguments,
+                        ],
+                    },
+                })
+            })
+
+            return actions
+        },
+    )
+
     connection.onRequest(
         GetTypeAtPositionRequest,
         (params: GetTypeAtPositionParams): GetTypeAtPositionResponse => {
@@ -1207,37 +1303,14 @@ connection.onInitialize(async (params: lsp.InitializeParams): Promise<lsp.Initia
         },
     )
 
-    connection.onExecuteCommand(params => {
-        if (params.command !== "tact/executeGetScopeProvider") return
-
-        const commandParams = params.arguments?.[0] as lsp.TextDocumentPositionParams | undefined
-        if (!commandParams) return "Invalid parameters"
-
-        const file = PARSED_FILES_CACHE.get(commandParams.textDocument.uri)
-        if (!file) {
-            return "File not found"
-        }
-
-        const node = nodeAtPosition(commandParams, file)
-        if (!node) {
-            return "Node not found"
-        }
-
-        const referent = new Referent(node, file)
-        const scope = referent.useScope()
-        if (!scope) return "Scope not found"
-        if (scope instanceof LocalSearchScope) return scope.toString()
-        return "GlobalSearchScope"
-    })
-
+    // noinspection JSUnusedLocalSymbols
     const _needed = TypeInferer.inferType
 
     console.info("Tact language server is ready!")
 
     return {
         capabilities: {
             textDocumentSync: lsp.TextDocumentSyncKind.Incremental,
-            // codeActionProvider: true,
             documentSymbolProvider: true,
             workspaceSymbolProvider: true,
             definitionProvider: true,
@@ -1269,8 +1342,11 @@ connection.onInitialize(async (params: lsp.InitializeParams): Promise<lsp.Initia
             codeLensProvider: {
                 resolveProvider: false,
             },
+            codeActionProvider: {
+                codeActionKinds: [lsp.CodeActionKind.QuickFix],
+            },
             executeCommandProvider: {
-                commands: ["tact/executeGetScopeProvider"],
+                commands: [...["tact/executeGetScopeProvider"], ...intentions.map(it => it.id)],
             },
         },
     }