src: expand \n to a newline in double quote string

doc/api/cli.md

@@ -666,6 +666,10 @@ of `--enable-source-maps`.
 
 <!-- YAML
 added: v20.6.0
+changes:
+  - version: REPLACEME
+    pr-url: https://github.com/nodejs/node/pull/51289
+    description: Add support to multi-line values.
 -->
 
 Loads environment variables from a file relative to the current directory,
@@ -702,6 +706,20 @@ They are omitted from the values.
 USERNAME="nodejs" # will result in `nodejs` as the value.
 ```
 
+Multi-line values are supported:
+
+```text
+MULTI_LINE="THIS IS
+A MULTILINE"
+# will result in `THIS IS\nA MULTILINE` as the value.
+```
+
+Export keyword before a key is ignored:
+
+```text
+export USERNAME="nodejs" # will result in `nodejs` as the value.
+```
+
 ### `-e`, `--eval "script"`
 
 <!-- YAML

src/node_dotenv.cc

@@ -102,8 +102,8 @@ Local<Object> Dotenv::ToObject(Environment* env) {
 }
 
 void Dotenv::ParseContent(const std::string_view content) {
-  using std::string_view_literals::operator""sv;
-  auto lines = SplitString(content, "\n"sv);
+  std::string lines = std::string(content);
+  lines = std::regex_replace(lines, std::regex("\r\n?"), "\n");
 
   std::smatch match;
   while (std::regex_search(lines, match, LINE)) {
@@ -131,7 +131,6 @@ void Dotenv::ParseContent(const std::string_view content) {
     store_.insert_or_assign(std::string(key), value);
     lines = match.suffix();
   }
-
 }
 
 Dotenv::ParseResult Dotenv::ParsePath(const std::string_view path) {
@@ -151,7 +150,7 @@ Dotenv::ParseResult Dotenv::ParsePath(const std::string_view path) {
     uv_fs_req_cleanup(&close_req);
   });
 
-  std::string lines{};
+  std::string result{};
   char buffer[8192];
   uv_buf_t buf = uv_buf_init(buffer, sizeof(buffer));
 
@@ -165,11 +164,11 @@ Dotenv::ParseResult Dotenv::ParsePath(const std::string_view path) {
     if (r <= 0) {
       break;
     }
-    lines.append(buf.base, r);
+    result.append(buf.base, r);
   }
 
   ParseContent(result);
-  return true;
+  return ParseResult::Valid;
 }
 
 void Dotenv::AssignNodeOptionsIfAvailable(std::string* node_options) {
@@ -180,9 +179,10 @@ void Dotenv::AssignNodeOptionsIfAvailable(std::string* node_options) {
   }
 }
 
-std::string Dotenv::trim_quotes(std::string str) {
+std::string_view Dotenv::trim_quotes(std::string_view str) {
   static const std::unordered_set<char> quotes = {'"', '\'', '`'};
-  if (str.size() >= 2 && quotes.count(str[0]) && quotes.count(str.back())) {
+  if (str.size() >= 2 && quotes.count(str.front()) &&
+      quotes.count(str.back())) {
     str = str.substr(1, str.size() - 2);
   }
   return str;

src/node_dotenv.h

@@ -32,7 +32,7 @@ class Dotenv {
 
  private:
   std::map<std::string, std::string> store_;
-  std::string trim_quotes(std::string str);
+  std::string_view trim_quotes(std::string_view str);
 };
 
 }  // namespace node

test/fixtures/dotenv/valid.env

@@ -20,6 +20,9 @@ BACKTICKS_SPACED=`    backticks    `
 DOUBLE_QUOTES_INSIDE_BACKTICKS=`double "quotes" work inside backticks`
 SINGLE_QUOTES_INSIDE_BACKTICKS=`single 'quotes' work inside backticks`
 DOUBLE_AND_SINGLE_QUOTES_INSIDE_BACKTICKS=`double "quotes" and single 'quotes' work inside backticks`
+EXPAND_NEWLINES="expand\nnew\nlines"
+DONT_EXPAND_UNQUOTED=dontexpand\nnewlines
+DONT_EXPAND_SQUOTED='dontexpand\nnewlines'
 # COMMENTS=work
 INLINE_COMMENTS=inline comments # work #very #well
 INLINE_COMMENTS_SINGLE_QUOTES='inline comments outside of #singlequotes' # work

test/parallel/test-dotenv.js

@@ -52,6 +52,8 @@ assert.strictEqual(process.env.INLINE_COMMENTS_DOUBLE_QUOTES, 'inline comments o
 assert.strictEqual(process.env.INLINE_COMMENTS_BACKTICKS, 'inline comments outside of #backticks');
 // Treats # character as start of comment
 assert.strictEqual(process.env.INLINE_COMMENTS_SPACE, 'inline comments start with a');
+// ignore comment
+assert.strictEqual(process.env.COMMENTS, undefined);
 // Respects equals signs in values
 assert.strictEqual(process.env.EQUAL_SIGNS, 'equals==');
 // Retains inner quotes
@@ -70,10 +72,15 @@ assert.strictEqual(process.env.EMAIL, 'therealnerdybeast@example.tld');
 assert.strictEqual(process.env.SPACED_KEY, 'parsed');
 // Parse inline comments correctly when multiple quotes
 assert.strictEqual(process.env.EDGE_CASE_INLINE_COMMENTS, 'VALUE1');
-// Test multiple-line value
+// Test multi-line values with line breaks
 assert.strictEqual(process.env.MULTI_DOUBLE_QUOTED, 'THIS\nIS\nA\nMULTILINE\nSTRING');
 assert.strictEqual(process.env.MULTI_SINGLE_QUOTED, 'THIS\nIS\nA\nMULTILINE\nSTRING');
 assert.strictEqual(process.env.MULTI_BACKTICKED, 'THIS\nIS\nA\n"MULTILINE\'S"\nSTRING');
 assert.strictEqual(process.env.MULTI_NOT_VALID_QUOTE, '"');
 assert.strictEqual(process.env.MULTI_NOT_VALID, 'THIS');
+// Test that \n is expanded to a newline in double-quoted string
+assert.strictEqual(process.env.EXPAND_NEWLINES, 'expand\nnew\nlines');
+assert.strictEqual(process.env.DONT_EXPAND_UNQUOTED, 'dontexpand\\nnewlines');
+assert.strictEqual(process.env.DONT_EXPAND_SQUOTED, 'dontexpand\\nnewlines');
+// Ignore export before key
 assert.strictEqual(process.env.EXAMPLE, 'ignore export');

test/parallel/util-parse-env.js

@@ -17,23 +17,33 @@ const fs = require('node:fs');
     BACKTICKS_INSIDE_SINGLE: '`backticks` work inside single quotes',
     BACKTICKS_SPACED: '    backticks    ',
     BASIC: 'basic',
-    DOUBLE_AND_SINGLE_QUOTES_INSIDE_BACKTICKS: 'double "quotes" and single \'quotes\' work inside backticks',
+    DONT_EXPAND_SQUOTED: 'dontexpand\\nnewlines',
+    DONT_EXPAND_UNQUOTED: 'dontexpand\\nnewlines',
+    DOUBLE_AND_SINGLE_QUOTES_INSIDE_BACKTICKS: "double \"quotes\" and single 'quotes' work inside backticks",
     DOUBLE_QUOTES: 'double_quotes',
     DOUBLE_QUOTES_INSIDE_BACKTICKS: 'double "quotes" work inside backticks',
     DOUBLE_QUOTES_INSIDE_SINGLE: 'double "quotes" work inside single quotes',
     DOUBLE_QUOTES_SPACED: '    double quotes    ',
     DOUBLE_QUOTES_WITH_NO_SPACE_BRACKET: '{ port: $MONGOLAB_PORT}',
+    EDGE_CASE_INLINE_COMMENTS: 'VALUE1',
     EMAIL: 'therealnerdybeast@example.tld',
     EMPTY: '',
     EMPTY_BACKTICKS: '',
     EMPTY_DOUBLE_QUOTES: '',
     EMPTY_SINGLE_QUOTES: '',
     EQUAL_SIGNS: 'equals==',
+    EXAMPLE: 'ignore export',
+    EXPAND_NEWLINES: 'expand\nnew\nlines',
     INLINE_COMMENTS: 'inline comments',
     INLINE_COMMENTS_BACKTICKS: 'inline comments outside of #backticks',
     INLINE_COMMENTS_DOUBLE_QUOTES: 'inline comments outside of #doublequotes',
     INLINE_COMMENTS_SINGLE_QUOTES: 'inline comments outside of #singlequotes',
     INLINE_COMMENTS_SPACE: 'inline comments start with a',
+    MULTI_BACKTICKED: 'THIS\nIS\nA\n"MULTILINE\'S"\nSTRING',
+    MULTI_DOUBLE_QUOTED: 'THIS\nIS\nA\nMULTILINE\nSTRING',
+    MULTI_NOT_VALID: 'THIS',
+    MULTI_NOT_VALID_QUOTE: '"',
+    MULTI_SINGLE_QUOTED: 'THIS\nIS\nA\nMULTILINE\nSTRING',
     RETAIN_INNER_QUOTES: '{"foo": "bar"}',
     RETAIN_INNER_QUOTES_AS_BACKTICKS: '{"foo": "bar\'s"}',
     RETAIN_INNER_QUOTES_AS_STRING: '{"foo": "bar"}',
@@ -42,7 +52,7 @@ const fs = require('node:fs');
     SINGLE_QUOTES_INSIDE_DOUBLE: "single 'quotes' work inside double quotes",
     SINGLE_QUOTES_SPACED: '    single quotes    ',
     SPACED_KEY: 'parsed',
-    TRIM_SPACE_FROM_UNQUOTED: 'some spaced out string'
+    TRIM_SPACE_FROM_UNQUOTED: 'some spaced out string',
   });
 }