From 810673ee2ef3547480ed21e7af5d6ce96e133278 Mon Sep 17 00:00:00 2001
From: Radon Rosborough <radon.neon@gmail.com>
Date: Mon, 28 Sep 2020 19:36:27 -0700
Subject: [PATCH] [#24] New language: Flex

---
 backend/src/langs.ts                | 25 +++++++++++++++++++++++++
 backend/src/test-runner.ts          |  4 +++-
 scripts/docker-install-phase3b.bash |  4 ++++
 3 files changed, 32 insertions(+), 1 deletion(-)

diff --git a/backend/src/langs.ts b/backend/src/langs.ts
index 69c7283..2c5ede8 100644
--- a/backend/src/langs.ts
+++ b/backend/src/langs.ts
@@ -1132,6 +1132,31 @@ USE: io
       input: `echo $x`,
     },
     template: `echo "Hello, world!"
+`,
+  },
+  flex: {
+    aliases: ["lex"],
+    name: "Flex",
+    main: "main.lex",
+    compile: "lex -o main.c main.lex && clang main.c -o main",
+    run: "echo 'Reading from stdin, ctrl+D to end input...' >&2 && ./main",
+    helloInput: "EOF",
+    template: `%{
+#include <stdio.h>
+%}
+
+%%
+%%
+
+int yywrap() {
+  printf("Hello, world!\\n");
+  return 1;
+}
+
+int main() {
+  yylex();
+  return 0;
+}
 `,
   },
   forth: {
diff --git a/backend/src/test-runner.ts b/backend/src/test-runner.ts
index 4cfb26c..95417cd 100644
--- a/backend/src/test-runner.ts
+++ b/backend/src/test-runner.ts
@@ -31,7 +31,9 @@ function findPosition(str: string, idx: number) {
 
 async function sendInput(send: (msg: any) => any, input: string) {
   for (const line of input.split("\n")) {
-    if (line.startsWith("DELAY:")) {
+    if (line === "EOF") {
+      send({ event: "terminalInput", input: "\u0004" });
+    } else if (line.startsWith("DELAY:")) {
       const delay = parseFloat(line.replace(/DELAY: */, ""));
       if (Number.isNaN(delay)) continue;
       await new Promise((resolve) =>
diff --git a/scripts/docker-install-phase3b.bash b/scripts/docker-install-phase3b.bash
index 9e46d98..f01ff5a 100755
--- a/scripts/docker-install-phase3b.bash
+++ b/scripts/docker-install-phase3b.bash
@@ -35,6 +35,10 @@ fsharp
 # Fish
 fish
 
+# Flex
+flex
+flex-doc
+
 # FORTRAN
 flang