src: allow absolute paths for --env-file

Author: anonrig

src/node.cc

@@ -124,6 +124,7 @@
 #include <cstdio>
 #include <cstdlib>
 #include <cstring>
+#include <filesystem>
 
 #include <string>
 #include <tuple>
@@ -844,10 +845,15 @@ static ExitCode InitializeNodeWithArgsInternal(
   auto file_path = node::Dotenv::GetPathFromArgs(*argv);
 
   if (file_path.has_value()) {
-    auto cwd = Environment::GetCwd(Environment::GetExecPath(*argv));
-    std::string path = cwd + kPathSeparator + file_path.value();
     CHECK(!per_process::v8_initialized);
-    per_process::dotenv_file.ParsePath(path);
+
+    if (file_path->is_absolute()) {
+      per_process::dotenv_file.ParsePath(file_path->string());
+    } else {
+      auto cwd = Environment::GetCwd(Environment::GetExecPath(*argv));
+      std::string path = cwd + kPathSeparator + file_path->string();
+      per_process::dotenv_file.ParsePath(path);
+    }
     per_process::dotenv_file.AssignNodeOptionsIfAvailable(&node_options);
   }
 

src/node_dotenv.cc

@@ -8,7 +8,7 @@ namespace node {
 using v8::NewStringType;
 using v8::String;
 
-std::optional<std::string> Dotenv::GetPathFromArgs(
+std::optional<std::filesystem::path> Dotenv::GetPathFromArgs(
     const std::vector<std::string>& args) {
   std::string_view flag = "--env-file";
   // Match the last `--env-file`
@@ -26,7 +26,7 @@ std::optional<std::string> Dotenv::GetPathFromArgs(
   auto equal_char = path->find('=');
 
   if (equal_char != std::string::npos) {
-    return path->substr(equal_char + 1);
+    return std::filesystem::path(path->substr(equal_char + 1));
   }
 
   auto next_arg = std::prev(path);
@@ -35,7 +35,7 @@ std::optional<std::string> Dotenv::GetPathFromArgs(
     return std::nullopt;
   }
 
-  return *next_arg;
+  return std::filesystem::path(*next_arg);
 }
 
 void Dotenv::SetEnvironment(node::Environment* env) {

src/node_dotenv.h

@@ -5,6 +5,7 @@
 
 #include "util-inl.h"
 
+#include <filesystem>
 #include <map>
 #include <optional>
 
@@ -23,7 +24,7 @@ class Dotenv {
   void AssignNodeOptionsIfAvailable(std::string* node_options);
   void SetEnvironment(Environment* env);
 
-  static std::optional<std::string> GetPathFromArgs(
+  static std::optional<std::filesystem::path> GetPathFromArgs(
       const std::vector<std::string>& args);
 
  private:

test/parallel/test-dotenv-edge-cases.js

@@ -2,10 +2,12 @@
 
 const common = require('../common');
 const assert = require('node:assert');
+const path = require('node:path');
 const { describe, it } = require('node:test');
 
 const validEnvFilePath = '../fixtures/dotenv/valid.env';
 const relativePath = '../fixtures/dotenv/node-options.env';
+const absolutePath = path.join(__dirname, relativePath);
 
 describe('.env supports edge cases', () => {
 
@@ -35,4 +37,17 @@ describe('.env supports edge cases', () => {
     assert.strictEqual(child.code, 0);
   });
 
+  it('should support absolute paths', async () => {
+    const code = `
+      require('assert').strictEqual(process.env.CUSTOM_VARIABLE, 'hello-world');
+    `.trim();
+    const child = await common.spawnPromisified(
+      process.execPath,
+      [ `--env-file=${absolutePath}`, '--eval', code ],
+      { cwd: __dirname },
+    );
+    assert.strictEqual(child.stderr, '');
+    assert.strictEqual(child.code, 0);
+  });
+
 });