Windows support (wip): target layer, Microsoft x64 ABI, portable runtime, CI

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tests/run.sh

@@ -17,7 +17,7 @@ for f in run/*.fch; do
     want="${f%.fch}.out"
     input="${f%.fch}.in"
     [ -f "$input" ] || input=/dev/null
-    got=$("$FINCH" run "$f" < "$input" 2>&1)
+    got=$("$FINCH" run "$f" < "$input" 2>&1 | tr -d '\r')   # Windows ends lines with \r\n
     if [ "$got" != "$(cat "$want")" ]; then
         failed=$((failed + 1))
         echo "FAIL $f"
@@ -41,6 +41,7 @@ for f in fail/*.fch; do
     expect=$(head -1 "$f" | sed -n 's|^// expect: ||p')
     got=$("$FINCH" run "$f" < /dev/null 2>&1)
     status=$?
+    got=$(echo "$got" | tr -d '\r')
     if [ $status -ne 0 ] && [[ "$got" == *"$expect"* ]]; then
         pass=$((pass + 1))
     else

tests/run/files.fch

@@ -1,9 +1,10 @@
 fn main() {
-    path := "/tmp/finch_test_file.txt"
+    path := "finch_test_file.txt"
     ok := write_file(path, "line one\nline two\n")
     print(ok, file_exists(path))
     text := read_file(path)
     lines := text.trim().split("\n")
     print(lines, lines.len)
-    print(file_exists("/definitely/not/here"))
+    print(delete_file(path), file_exists(path))
+    print(file_exists("definitely/not/here"))
 }

tests/run/files.out

@@ -1,3 +1,4 @@
 true true
 ["line one", "line two"] 2
+true false
 false

tests/run/pointers.out

@@ -1,4 +1,4 @@
 42
 2 1
 99
-true true (nil)
+true true null

tests/windows.sh

@@ -0,0 +1,50 @@
+#!/usr/bin/env bash
+# Cross-compiles every test for Windows (x86_64-w64-mingw32) and runs it under Wine.
+# Needs x86_64-w64-mingw32-gcc and wine, e.g.:
+#   nix-shell -p pkgsCross.mingwW64.buildPackages.gcc wine64 --run tests/windows.sh
+# (On a real Windows machine, use tests/run.sh with finch.exe instead.)
+set -u
+cd "$(dirname "$0")"
+FINCH=${FINCH:-../build/finch}
+export WINEDEBUG=-all
+pass=0; failed=0
+tmp=$(mktemp -d)
+trap 'rm -rf "$tmp"' EXIT
+
+run_exe() {  # exe, stdin -> output without Windows' \r
+    wine "$1" < "$2" 2>&1 | tr -d '\r'
+}
+
+for f in run/*.fch; do
+    grep -q "^fn main" "$f" || continue
+    input="${f%.fch}.in"
+    [ -f "$input" ] || input=/dev/null
+    exe="$tmp/$(basename "${f%.fch}").exe"
+    if ! "$FINCH" build "$f" --target windows -o "$exe" > "$tmp/err" 2>&1; then
+        failed=$((failed + 1)); echo "FAIL (build) $f"; head -5 "$tmp/err"; continue
+    fi
+    got=$(run_exe "$exe" "$input")
+    if [ "$got" == "$(cat "${f%.fch}.out")" ]; then
+        pass=$((pass + 1))
+    else
+        failed=$((failed + 1)); echo "FAIL $f"; diff <(echo "$got") "${f%.fch}.out" | head -10
+    fi
+done
+
+for f in fail/*.fch; do
+    expect=$(head -1 "$f" | sed -n 's|^// expect: ||p')
+    exe="$tmp/$(basename "${f%.fch}").exe"
+    if got=$("$FINCH" build "$f" --target windows -o "$exe" 2>&1); then
+        got=$(run_exe "$exe" /dev/null); status=$?
+        status=$( [ -n "$got" ] && echo 1 || echo 0 )
+    else
+        status=1
+    fi
+    if [[ "$got" == *"$expect"* ]]; then
+        pass=$((pass + 1))
+    else
+        failed=$((failed + 1)); echo "FAIL $f (wanted: $expect)"; echo "$got" | head -5
+    fi
+done
+echo "windows (wine): $pass passed, $failed failed"
+[ $failed -eq 0 ]