dotenv: fix env-file parsing

Author: lubosmato

src/node_dotenv.cc

@@ -151,7 +151,17 @@ void Dotenv::ParseContent(const std::string_view input) {
     // Expand new line if \n it's inside double quotes
     // Example: EXPAND_NEWLINES = 'expand\nnew\nlines'
     if (content.front() == '"') {
-      auto closing_quote = content.find(content.front(), 1);
+      std::size_t closing_quote = 0;
+      do {
+        closing_quote = content.find(content.front(), closing_quote + 1);
+        if (closing_quote == std::string_view::npos) {
+          break;
+        }
+        if (closing_quote > 0 && content[closing_quote - 1] != '\\') {
+          break;
+        }
+      } while (closing_quote != std::string_view::npos);
+
       if (closing_quote != std::string_view::npos) {
         value = content.substr(1, closing_quote - 1);
         std::string multi_line_value = std::string(value);
@@ -163,6 +173,13 @@ void Dotenv::ParseContent(const std::string_view input) {
           pos += 1;
         }
 
+        pos = 0;
+        while ((pos = multi_line_value.find(R"(\")", pos)) !=
+               std::string_view::npos) {
+          multi_line_value.replace(pos, 2, "\"");
+          pos += 1;
+        }
+
         store_.insert_or_assign(std::string(key), multi_line_value);
         content.remove_prefix(content.find('\n', closing_quote + 1));
         continue;

test/fixtures/dotenv/valid.env

@@ -43,6 +43,9 @@ EMAIL=therealnerdybeast@example.tld
     SPACED_KEY = parsed
 EDGE_CASE_INLINE_COMMENTS="VALUE1" # or "VALUE2" or "VALUE3"
 
+ALL_QUOTES="this 'has' all \"quotes\" in `value` and double quotes around"
+ALL_QUOTES_EXPAND_NEWLINES="this\n'has'\nall\n\"quotes\"\nin\n`value`\nand\nmultilines\nto\nexpand"
+
 MULTI_DOUBLE_QUOTED="THIS
 IS
 A

test/parallel/test-dotenv.js

@@ -82,3 +82,6 @@ assert.strictEqual(process.env.DONT_EXPAND_SQUOTED, 'dontexpand\\nnewlines');
 assert.strictEqual(process.env.EXPORT_EXAMPLE, 'ignore export');
 // Ignore spaces before double quotes to avoid quoted strings as value
 assert.strictEqual(process.env.SPACE_BEFORE_DOUBLE_QUOTES, 'space before double quotes');
+assert.strictEqual(process.env.ALL_QUOTES, 'this \'has\' all "quotes" in `value` and double quotes around');
+assert.strictEqual(process.env.ALL_QUOTES_EXPAND_NEWLINES, 'this\n\'has\'\nall\n"quotes"\nin\n`value`\nand\nmultilines\nto\nexpand');
+