feat: add a simple REPL to print lexing results (#2)

## What does this PR do?

add a simple REPL to print lexing results

.github/dependabot.yml

@@ -0,0 +1,7 @@
+---
+version: 2
+updates:
+  - package-ecosystem: "github-actions"
+    directory: "/"
+    schedule:
+      interval: "monthly"

.github/workflows/check-cc.yaml

@@ -0,0 +1,18 @@
+name: Check for conventional commit compliance
+
+on:
+  pull_request:
+    types: [opened, ready_for_review, edited]
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  check-cc:
+    name: Check for conventional commit compliance
+    runs-on: ubuntu-latest
+    steps:
+      - uses: agenthunt/[email protected]
+        with:
+          pr-title-regex: '^(build|chore|ci|docs|feat|fix|perf|refactor|revert|style|test)(\((\w|-)+\))?(!)?:.*'

.github/workflows/go.yaml → .github/workflows/ci.yaml

@@ -1,7 +1,4 @@
-# This workflow will build a golang project
-# For more information see: https://docs.github.com/en/actions/automating-builds-and-tests/building-and-testing-go
-
-name: Go
+name: Lint, build, test
 
 on:
   push:
@@ -11,9 +8,13 @@ on:
     branches:
       - main
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
 jobs:
-  build-test:
-    runs-on: ubuntu-22.04
+  lint-build-test:
+    runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v4
 
@@ -36,4 +37,4 @@ jobs:
     - name: test
       run: |
         go install github.com/onsi/ginkgo/v2/ginkgo
-        ginkgo run -r -cover
+        ginkgo run -r -race -cover

.github/workflows/release.yaml

@@ -1,22 +1,18 @@
-name: Bump version
+name: Release
 
 on:
-  pull_request:
-    types:
-      - closed
+  push:
     branches:
       - main
 
 jobs:
   tag-release:
-    if: github.event.pull_request.merged == true
-    runs-on: ubuntu-22.04
+    runs-on: ubuntu-latest
     permissions:
       contents: write
     steps:
     - uses: actions/checkout@v4
       with:
-        ref: ${{ github.event.pull_request.merge_commit_sha }}
         fetch-depth: '0'
 
     - name: Bump version and push tag

README.md

@@ -30,8 +30,8 @@ An interpreted language written in Go
 - [ ] feat: add logical operators ||， &&
 - [ ] feat: add bitwise operators ^, |, &
 - [ ] refactor: unary operators, binary operators, ternary operators
-
-
+- [ ] feat: use Cobra to enable multiple modes when launching the REPL
+- [ ] feat: use quit(), exit(), or Ctrl-D to exit
 
 
 

cmd/root.go

@@ -5,8 +5,11 @@ package cmd
 
 import (
 	"fmt"
+	"log"
 	"os"
+	"os/user"
 
+	"github.com/Aden-Q/monkey/internal/repl"
 	"github.com/spf13/cobra"
 )
 
@@ -33,7 +36,15 @@ func Execute() {
 }
 
 func run(cmd *cobra.Command, args []string) {
-	fmt.Println("Hello, World!")
+	user, err := user.Current()
+	if err != nil {
+		log.Fatalf("user error: %v", err)
+	}
+
+	fmt.Printf("Hello %s! This is the Monkey programming language!\n", user.Username)
+
+	r := repl.New(repl.Config{})
+	r.Start(os.Stdin, os.Stdout)
 }
 
 func init() {

internal/repl/repl.go

@@ -0,0 +1,46 @@
+package repl
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+
+	"github.com/Aden-Q/monkey/internal/lexer"
+	"github.com/Aden-Q/monkey/internal/token"
+)
+
+const PROMPT = ">>> "
+
+type REPL interface {
+	Start(in io.ReadCloser, out io.WriteCloser)
+}
+
+type Config struct {
+}
+
+type repl struct {
+}
+
+func New(config Config) REPL {
+	return &repl{}
+}
+
+func (r *repl) Start(in io.ReadCloser, out io.WriteCloser) {
+	scanner := bufio.NewScanner(in)
+
+	for {
+		fmt.Print(PROMPT)
+
+		scanned := scanner.Scan()
+		if !scanned {
+			return
+		}
+
+		line := scanner.Text()
+		l := lexer.New(line)
+
+		for tok, ok := l.NextToken(); ok && tok.Type != token.EOF; tok, ok = l.NextToken() {
+			fmt.Printf("%+v\n", tok)
+		}
+	}
+}

internal/repl/repl_suite_test.go

@@ -0,0 +1,13 @@
+package repl_test
+
+import (
+	"testing"
+
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+)
+
+func TestRepl(t *testing.T) {
+	RegisterFailHandler(Fail)
+	RunSpecs(t, "Repl Suite")
+}

internal/repl/repl_test.go

@@ -0,0 +1,10 @@
+package repl_test
+
+import (
+	. "github.com/onsi/ginkgo/v2"
+	_ "github.com/onsi/gomega"
+)
+
+var _ = Describe("Repl", func() {
+
+})

justfile

@@ -6,15 +6,15 @@
 @vendor:
   go mod vendor
 
-# run all tests with ginkgo
+# run all unit tests with ginkgo
 @test:
-  ginkgo run -r -cover -coverprofile=coverage.out
+  ginkgo run -r -race -cover -coverprofile=coverage.out
 
 # build a binary executable
 @build:
   go build .
 
-# run the Monkey language interpreter in an interactive shell env
+# run the Monkey language interpreter in interactive mode
 @run:
   go run main.go