#!/bin/bash

LANG_DIR="$1"

shift

HAS_LANG_FILES=1

if echo "$LANG_DIR"/lang-*.js | egrep -q "[*]" >& /dev/null; then

HAS_LANG_FILES=0

fi

if [ -n "$*" ] || [ -z "$LANG_DIR" ] || ! (( $HAS_LANG_FILES )); then

echo "Usage: $0 <LANG_DIR>"

echo

echo "Dumps lines of the form"

echo " $LANG_DIR/lang-foo.js $LANG_DIR/lang-<extension>.js"

echo "where the first element is a path name under LANG_DIR"

echo "and the second is the name of a language extension for which"

echo "it registers an extension."

exit -1

fi

if [ -z "$JS_INTERPRETER" ]; then

JS_INTERPRETER="js17"

fi

if ! which "$JS_INTERPRETER" >& /dev/null; then

echo "\$JS_INTERPRETER ( '$JS_INTERPRETER' ) is not on the \$PATH."

echo "It should be an executable that loads each argument as a JS file"

echo "and runs them in a context where the print function dumps a string"

echo "to stdout."

exit -1

fi

for JS in "$LANG_DIR"/lang-*.js; do

# Run the language handler in a context where PR.registerLangHandler

# dumps out the handler names without doing anything else, and

# then use a perl script that prepends each handler with the basename

# of the JS file.

# The JS interpreter is run with STDIN of /dev/null so that it does not

# hand waiting for REPL input.

("$JS_INTERPRETER" \

-e '

var window = this;

var PR = {

registerLangHandler: function (_, exts) {

for (var i = 0, n = exts.length; i < n; ++i) {

var handler = String(exts[i]);

if (/^\w+$/.test(handler)) {

print(handler);

}

}

},

createSimpleLexer: function () {},

sourceDecorator: function () {}

};

' \

-f "$JS" \

< /dev/null \

|| echo "Failed to execute $JS" 1>&2 ) \

| perl -e '$JS=shift;' \

-e 'use File::Basename; $DIR=dirname($JS);' \

-e 'while (<STDIN>) { s/^\w+$/$JS $DIR\/lang-$&.js/; print; }' \

"$JS"

done