Add stdlib test importing every stdlib module + fix stdlib (#795)

Resolves #614 by adding a stdlib test that imports every single (common)
stdlib module.

Let's add [ACME](https://en.wikipedia.org/wiki/Acme_Corporation) (in our
context "All Common Modules in Effekt" :)) to the stdlib tests: just
import and compile all modules.

This revealed 3 different bugs in stdlib + codegen bugs on LLVM (moved
to #801).

Author: jiribenes

.github/workflows/acme.yml

@@ -0,0 +1,52 @@
+name: Check every stdlib module is compiled (acme)
+
+on:
+  pull_request:
+    paths:
+      - 'libraries/common/**'
+
+jobs:
+  check-stdlib-sync:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Generate acme and test for differences
+        id: generate-acme
+        shell: bash
+        run: |
+          # Function to convert file path to module import path
+          path_to_module() {
+            local filepath="$1"
+            # Remove libraries/common/ prefix and .effekt suffix
+            local module_path="${filepath#libraries/common/}"
+            module_path="${module_path%.effekt}"
+            echo "$module_path"
+          }
+
+          # Find all .effekt files in libraries/common, excluding acme.effekt
+          MODULES=$(find libraries/common -type f -name "*.effekt" | sort | while read -r file; do
+            path_to_module "$file"
+          done)
+
+          # Create the new acme.effekt content
+          {
+            echo "/// This module is auto-generated and checked in CI."
+            echo "/// It imports **every** stdlib module: ACME = All Common Modules in Effekt"
+            echo "module acme"
+            echo ""
+            for module in $MODULES; do
+              echo "import $module"
+            done
+            echo ""
+            echo "def main() = ()"
+          } > generated-acme.effekt
+
+          # Compare files, ignoring whitespace, blank lines, and line ending differences
+          if ! diff -Bbq examples/stdlib/acme.effekt generated-acme.effekt; then
+            echo "::error::The stdlib import file (examples/stdlib/acme.effekt) is out of sync with the modules in libraries/common."
+            echo "Differences found:"
+            diff -Bu examples/stdlib/acme.effekt generated-acme.effekt
+            exit 1
+          fi

effekt/jvm/src/test/scala/effekt/StdlibTests.scala

@@ -49,5 +49,9 @@ class StdlibLLVMTests extends StdlibTests {
 
     // String comparison using `<`, `<=`, `>`, `>=` is not implemented yet on LLVM
     examplesDir / "stdlib" / "string" / "compare.effekt",
+
+    // Wrong codegen for negative types, see #801
+    examplesDir / "stdlib" / "json.effekt",
+    examplesDir / "stdlib" / "buffer.effekt",
   )
 }

examples/stdlib/acme.check

@@ -0,0 +1,37 @@
+/// This module is auto-generated and checked in CI.
+/// It imports **every** stdlib module: ACME = All Common Modules in Effekt
+module acme
+
+import args
+import array
+import bench
+import buffer
+import bytearray
+import char
+import dequeue
+import effekt
+import exception
+import io
+import io/console
+import io/error
+import io/filesystem
+import io/network
+import io/time
+import json
+import list
+import map
+import option
+import process
+import queue
+import ref
+import regex
+import result
+import scanner
+import seq
+import set
+import stream
+import string
+import test
+import tty
+
+def main() = ()

examples/stdlib/acme.effekt

@@ -0,0 +1,8 @@
+1
+false
+Some(17)
+Some(1)
+Some(2)
+Some(3)
+Some(4)
+Some(5)

examples/stdlib/buffer.check

@@ -0,0 +1,3 @@
+import buffer
+
+def main() = buffer::examples::main()

examples/stdlib/buffer.effekt

@@ -0,0 +1,65 @@
+	a
+
+a
+
+a
+b
+f
+
+{
+"x"
+:
+"Hallo"
+,
+"y"
+:
+null
+,
+"z"
+:
+12.3783
+}
+
+{
+"a"
+:
+null
+,
+"b"
+:
+[
+true
+,
+false
+,
+false
+,
+true
+]
+,
+"f"
+:
+12.532
+}
+
+{
+"a"
+:
+null
+,
+"b"
+:
+[
+true
+,
+false
+,
+false
+,
+true
+]
+,
+"f"
+:
+12.532
+}

examples/stdlib/json.check

@@ -0,0 +1,3 @@
+import json
+
+def main() = json::test::main()

examples/stdlib/json.effekt

@@ -34,7 +34,7 @@ def emptyBuffer[T](capacity: Int): Buffer[T] at {global} = {
 }
 def arrayBuffer[T](initialCapacity: Int): Buffer[T] at {global} = {
   // TODO allocate buffer (and array) into a region r.
-  val contents = emptyArray[T](initialCapacity)
+  val contents = array::allocate[T](initialCapacity)
   var head in global = 0
   var tail in global = 0
 
@@ -51,15 +51,15 @@ def arrayBuffer[T](initialCapacity: Int): Buffer[T] at {global} = {
     def read() = {
       if (buffer.empty?) None()
       else {
-        val result: T = contents.remove(head).getOrElse { <> };
+        val result: T = contents.unsafeGet(head);
         head = mod(head + 1, initialCapacity)
         Some(result)
       }
     }
     def write(el: T) = {
       if (buffer.full?) <> // raise(BufferOverflow())
 
-      contents.put(tail, el)
+      contents.unsafeSet(tail, el)
       tail = mod(tail + 1, initialCapacity)
     }
   }

libraries/common/buffer.effekt

@@ -57,14 +57,17 @@ def server(host: String, port: Int, handler: () => Unit / Socket at {io, async,
 
 namespace examples {
   def helloWorldApp(): Unit / Socket = {
-    val request = do receive();
+    val request = do receive().toString;
 
-    println("Received a request: " ++ request.toUTF8)
+    println("Received a request: " ++ request)
 
-    if (request.toUTF8.startsWith("GET /")) {
-      do send(fromUTF8("HTTP/1.1 200 OK\r\n\r\nHello from Effekt!"))
+    def respond(s: String): Unit / Socket =
+      do send(s.fromString)
+
+    if (request.startsWith("GET /")) {
+      respond("HTTP/1.1 200 OK\r\n\r\nHello from Effekt!")
     } else {
-      do send("HTTP/1.1 400 Bad Request\r\n\r\n".fromUTF8)
+      respond("HTTP/1.1 400 Bad Request\r\n\r\n")
     }
     do end()
   }