add doctest script

doctest.sh

@@ -0,0 +1,89 @@
+#!/usr/bin/env bash
+#
+# This file runs code snippets in doc/*.md files.
+
+set -e -o pipefail
+
+for arg in "$@"; do
+    if [[ "$arg" =~ ^- ]]; then
+        echo "Usage: $0 [doc/file1.md doc/file2.md ...]" >&2
+        exit 2
+    fi
+done
+
+if [ $# == 0 ]; then
+    files=(doc/*.md)
+else
+    files=("$@")
+fi
+
+if [[ "$OS" =~ Windows ]]; then
+    source activate
+    mingw32-make
+    jou="$PWD/jou.exe"
+else
+    make
+    jou="$PWD/jou"
+fi
+
+function slice()
+{
+    local first_lineno="$1"
+    local last_lineno="$2"
+    local num_lines=$((last_lineno - first_lineno + 1))
+    head -n $last_lineno | tail -n $num_lines
+}
+
+function generate_expected_output()
+{
+    local joufile="$1"
+
+    (grep -onH '# Warning: .*' "$joufile" || true) | sed -E s/'(.*):([0-9]*):# Warning: '/'compiler warning for file "test.jou", line \2: '/
+    (grep -onH '# Error: .*' "$joufile" || true) | sed -E s/'(.*):([0-9]*):# Error: '/'compiler error in file "\1", line \2: '/
+    (grep -oE '# Output:.*' "$joufile" || true) | sed -E s/'^# Output: ?'//
+}
+
+rm -rf tmp/doctest
+mkdir tmp/doctest
+
+for file in "${files[@]}"; do
+    echo "Extracting doctests from $file..."
+    mkdir tmp/doctest/"$(basename "$file")"
+
+    for start_marker_lineno in $(grep -n '^```python$' "$file" | cut -d: -f1); do
+        outfile="tmp/doctest/$(basename "$file")/$((start_marker_lineno + 1)).jou"
+        awk -v n=$start_marker_lineno '(/^```$/ && line > n) { stop=1 } (++line > n && !stop) { print }' "$file" > "$outfile"
+
+        # Do not test if there is no expected output/errors
+        if [ -z "$(generate_expected_output "$outfile")" ]; then
+            rm "$outfile"
+        fi
+    done
+done
+
+ntotal=$(ls -1 tmp/doctest/*/*.jou | wc -l)
+if [ $ntotal == 0 ]; then
+    echo "*** Error: no doctests found ***" >&2
+    exit 1
+fi
+echo "Running $ntotal doctests..."
+nfail=0
+
+cd tmp/doctest
+for file in */*.jou; do
+    echo "${file%.*}" | tr '/' ':'  # foo.md/123.jou --> foo.md:123
+    cp "$file" test.jou
+    if diff --text -u --color=always <(generate_expected_output test.jou | tr -d '\r') <( "$jou" test.jou 2>&1 || true | tr -d '\r'); then
+        echo "  ok"
+    else
+        ((nfail++)) || true
+    fi
+done
+
+echo ""
+echo ""
+
+echo "$((ntotal-nfail)) succeeded, $nfail failed"
+if [ $nfail != 0 ]; then
+    exit 1
+fi