escape single parenthesis when generating fdf files

index.js

@@ -177,6 +177,19 @@ class PdfTk {
         return new Buffer(str, encoding);
     }
 
+    /**
+     * Sanitizes fdf input
+     * @statuc
+     * @public
+     * @param {String} str - String to sanitize
+     * @returns {String} Sanitized string
+     */
+    static sanitizeForFdf(str) {
+        return str
+            .replace(/\(/g, '\\(')
+            .replace(/\)/g, '\\)');
+    }
+
     /**
      * Creates fdf file from JSON input.
      * Converts input values to binary buffer, which seems to allow PdfTk to render utf-8 characters.
@@ -208,15 +221,15 @@ class PdfTk {
                 ]);
                 body = Buffer.concat([
                     body,
-                    PdfTk.stringToBuffer(prop.toString(), 'binary'),
+                    PdfTk.stringToBuffer(PdfTk.sanitizeForFdf(prop.toString()), 'binary'),
                 ]);
                 body = Buffer.concat([
                     body,
                     PdfTk.stringToBuffer(')\n/V('),
                 ]);
                 body = Buffer.concat([
                     body,
-                    PdfTk.stringToBuffer(data[prop].toString(), 'binary'),
+                    PdfTk.stringToBuffer(PdfTk.sanitizeForFdf(data[prop].toString()), 'binary'),
                 ]);
                 body = Buffer.concat([
                     body,

pretest.js

@@ -24,6 +24,7 @@ const commands = [
     'test/files/form.pdf fill_form test/files/formwithnumber.fdf output test/files/filledformwithnumber.temp.pdf',
     'test/files/form.pdf fill_form test/files/form.fdf output test/files/filledformflat.temp.pdf flatten',
     'test/files/form.pdf fill_form test/files/form.blank.fdf output test/files/filledformempty.temp.pdf flatten',
+    'test/files/form.pdf fill_form test/files/form.escape.fdf output test/files/filledformescape.temp.pdf flatten',
     'test/files/form.pdf generate_fdf output test/files/form.temp.fdf',
     'test/files/form.pdf stamp test/files/logo.pdf output test/files/stamp.temp.pdf',
     'test/files/form.pdf multistamp test/files/logo.pdf output test/files/multistamp.temp.pdf',

test/files/form.escape.fdf

@@ -0,0 +1,24 @@
+%FDF-1.2
+%����
+1 0 obj
+<<
+/FDF
+<<
+/Fields [
+<<
+/V ([email protected])
+/T (email)
+>>
+<<
+/V (John Doe\))
+/T (name)
+>>]
+>>
+>>
+endobj
+trailer
+
+<<
+/Root 1 0 R
+>>
+%%EOF

test/fillForm.spec.js

@@ -135,6 +135,23 @@ describe('fillForm', function () {
             .catch(err => expect(err).to.be.null);
     });
 
+    it('should escape single parenthesis', function () {
+
+        const testFile = fs.readFileSync(path.join(__dirname, './files/filledformescape.temp.pdf'));
+        const input = path.join(__dirname, './files/form.pdf');
+
+        return pdftk
+            .input(input)
+            .fillForm({
+                name: 'John Doe)',
+                email: '[email protected]',
+            })
+            .flatten()
+            .output()
+            .then(buffer => expect(buffer.equals(testFile)).to.be.true)
+            .catch(err => expect(err).to.be.null);
+    });
+
     it('should catch an error if given a bad input path', function () {
 
         const input = path.join(__dirname, './files/doesnotexist.pdf');