Add conan.conanrc file to setup the conan user home

conans/paths/__init__.py

@@ -1,8 +1,9 @@
 # coding=utf-8
-
+from configparser import ConfigParser
 import os
 import platform
 
+
 if platform.system() == "Windows":
     from conans.util.windows import conan_expand_user
 else:
@@ -12,7 +13,22 @@
 
 
 def get_conan_user_home():
-    user_home = os.getenv("CONAN_HOME")
+    conanrc_home = None
+
+    conanrc_config = ConfigParser()
+    conanrc_file = conanrc_config.read(os.path.join(os.getcwd(), "conan.conanrc"))
+
+    if conanrc_file:
+        try:
+            init_section = conanrc_config["init"]
+            conanrc_home = init_section["conan_home"]
+        except KeyError:
+            pass
+
+    if conanrc_home and (conanrc_home[:2] in ("./", ".\\") or conanrc_home.startswith("..")):  # local
+        conanrc_home = os.path.abspath(os.path.join(os.getcwd(), conanrc_home))
+
+    user_home = conanrc_home or os.getenv("CONAN_HOME")
     if user_home is None:
         # the default, in the user home
         user_home = os.path.join(conan_expand_user("~"), DEFAULT_CONAN_HOME)

conans/test/unittests/paths/user_home_test.py

@@ -0,0 +1,35 @@
+import os
+
+from conans.paths import get_conan_user_home
+from conans.test.utils.test_files import temp_folder
+from conans.util.files import chdir
+
+
+def test_conanrc_abs_path_get_conan_user_home():
+    _temp_folder = temp_folder(path_with_spaces=True)
+    with chdir(_temp_folder):
+        with open(os.path.join(_temp_folder, "conan.conanrc"), 'w+') as file:
+            file.write(f'[init]\nconan_home={_temp_folder}\n')
+        conan_home = get_conan_user_home()
+        assert _temp_folder == conan_home
+
+
+def test_conanrc_local_path_get_conan_user_home():
+    _temp_folder = temp_folder(path_with_spaces=True)
+    subfolder = "subfolder inside temp"
+    with chdir(_temp_folder):
+        with open(os.path.join(_temp_folder, "conan.conanrc"), 'w+') as file:
+            file.write(f'[init]\nconan_home=.{os.sep}{subfolder}\n')
+        conan_home = get_conan_user_home()
+        assert str(os.path.join(_temp_folder, subfolder)) == conan_home
+
+
+def test_conanrc_local_outside_folder_path_get_conan_user_home():
+    _temp_folder = temp_folder(path_with_spaces=True)
+    folder1 = os.path.join(_temp_folder, "folder1")
+    os.mkdir(folder1)
+    with chdir(folder1):
+        with open(os.path.join(folder1, "conan.conanrc"), 'w+') as file:
+            file.write(f'[init]\nconan_home=..{os.sep}folder2\n')
+        conan_home = get_conan_user_home()
+        assert str(os.path.join(_temp_folder, "folder2")) == conan_home