From 83ee1446245e2b9226dc0d6ced7c0494f0e65d9f Mon Sep 17 00:00:00 2001
From: Alexander Grund <alexander.grund@tu-dresden.de>
Date: Wed, 12 Nov 2025 15:22:29 +0100
Subject: [PATCH 1/6] Implement more complete TOML parser in Cargo easyblock

Loosely parse everything that could be in a Cargo.toml file
---
 easybuild/easyblocks/generic/cargo.py | 118 ++++++++++++++++++++------
 test/easyblocks/easyblock_specific.py |  88 +++++++++++++++++++
 2 files changed, 181 insertions(+), 25 deletions(-)

diff --git a/easybuild/easyblocks/generic/cargo.py b/easybuild/easyblocks/generic/cargo.py
index b92bc9bdd61..f6669804d04 100755
--- a/easybuild/easyblocks/generic/cargo.py
+++ b/easybuild/easyblocks/generic/cargo.py
@@ -37,6 +37,7 @@
 import tempfile
 from glob import glob
 from pathlib import Path
+from typing import Dict, List, Union
 
 import easybuild.tools.environment as env
 import easybuild.tools.systemtools as systemtools
@@ -78,6 +79,88 @@
 CARGO_CHECKSUM_JSON = '{{"files": {{}}, "package": "{checksum}"}}'
 
 
+def parse_toml_list(value: str) -> List[str]:
+    """Split a TOML list value"""
+    if not value.startswith('[') or not value.endswith(']'):
+        raise ValueError(f"'{value}' is not a TOML list")
+    value = value[1:-1].strip()
+    simple_str_markers = ('"""', "'''", "'")
+    current_value = ''
+    result = []
+    while value:
+        for marker in simple_str_markers:
+            if value.startswith(marker):
+                idx = value.index(marker, len(marker))
+                current_value += value[:idx + len(marker)]
+                value = value[idx + len(marker):].lstrip()
+                break
+        else:
+            if value.startswith('"'):
+                m = re.match(r'".*?(?<!\\)"', value, re.M)
+                current_value += m[0]
+                value = value[m.end():].lstrip()
+        # Not inside a string here
+        if value.startswith(','):
+            result.append(current_value)
+            current_value = ''
+            value = value[1:].lstrip()
+        else:
+            m = re.search('"|\'|,', value)
+            if m:
+                current_value += value[:m.start()].strip()
+                value = value[m.end():]
+            else:
+                current_value += value.strip()
+                break
+    if current_value:
+        result.append(current_value)
+    return result
+
+
+def parse_toml(file: Path) -> Dict[str, str]:
+    """Minimally parse a TOML file into sections, keys and values
+
+    Values will be the raw strings (including quotes for string-typed values)"""
+
+    result: Dict[str, Union[str, List[str]]] = {}
+    pending_key = None
+    pending_value = None
+    expected_end = None
+    current_section = None
+    content = read_file(file)
+    try:
+        for raw_line in content.splitlines():
+            line: str = raw_line.split("#", 1)[0].strip()
+            if not line:
+                continue
+            if pending_key is None and line.startswith("[") and line.endswith("]"):
+                current_section = line.strip()[1:-1].strip()
+                result.setdefault(current_section, {})
+                continue
+            if pending_key is None:
+                key, val = line.split("=", 1)
+                pending_key = key.strip()
+                pending_value = val.strip()
+                if pending_value.startswith('['):
+                    expected_end = ']'
+                elif pending_value.startswith('{'):
+                    expected_end = '}'
+                elif pending_value.startswith('"""'):
+                    expected_end = '"""'
+                elif pending_value.startswith("'''"):
+                    expected_end = "'''"
+                else:
+                    expected_end = None
+            else:
+                pending_value += '\n' + line
+            if expected_end is None or pending_value.endswith(expected_end):
+                result[current_section][pending_key] = pending_value.strip()
+                pending_key = None
+    except Exception as e:
+        raise ValueError(f'Failed to parse {file} ({content}): {e}')
+    return result
+
+
 def get_workspace_members(crate_dir: Path):
     """Find all members of a cargo workspace in crate_dir.
 
@@ -87,10 +170,10 @@ def get_workspace_members(crate_dir: Path):
     has_package determines if it is a virtual workspace ([workspace] and no [package])
     workspace-members are all members (subfolder names) if it is a workspace, otherwise None
     """
-    cargo_toml = crate_dir / 'Cargo.toml'
-    lines = [line.strip() for line in read_file(cargo_toml).splitlines()]
+    cargo_toml = parse_toml(crate_dir / 'Cargo.toml')
+
     # A virtual (workspace) manifest has no [package], but only a [workspace] section.
-    has_package = '[package]' in lines
+    has_package = 'package' in cargo_toml
 
     # We are looking for this:
     # [workspace]
@@ -101,30 +184,15 @@ def get_workspace_members(crate_dir: Path):
     # ]
 
     try:
-        start_idx = lines.index('[workspace]')
-    except ValueError:
+        workspace = cargo_toml['workspace']
+    except KeyError:
         return has_package, None
-    # Find "members = [" and concatenate the value, stop at end of section or file
-    member_str = None
-    for line in lines[start_idx + 1:]:
-        if line.startswith('#'):
-            continue  # Skip comments
-        if re.match(r'\[\w+\]', line):
-            break  # New section
-        if member_str is None:
-            m = re.match(r'members\s+=\s+\[', line)
-            if m:
-                member_str = line[m.end():]
-        else:
-            member_str += line
-        # Stop if we reach the end of the list
-        if member_str is not None and member_str.endswith(']'):
-            member_str = member_str[:-1]
-            break
-    if member_str is None:
+    try:
+        member_strs = parse_toml_list(workspace['members'])
+    except (KeyError, ValueError):
         raise EasyBuildError('Failed to find members in %s', cargo_toml)
-    # Split at commas after removing possibly trailing ones and remove the quotes
-    members = [member.strip().strip('"') for member in member_str.rstrip(',').split(',')]
+    # Remove the quotes
+    members = [member.strip('"') for member in member_strs]
     # Sanity check that we didn't pick up anything unexpected
     invalid_members = [member for member in members if not re.match(r'(\w|-)+', member)]
     if invalid_members:
diff --git a/test/easyblocks/easyblock_specific.py b/test/easyblocks/easyblock_specific.py
index e18c7b93ee1..9f03ec6d073 100644
--- a/test/easyblocks/easyblock_specific.py
+++ b/test/easyblocks/easyblock_specific.py
@@ -36,10 +36,12 @@
 import textwrap
 from io import StringIO
 from unittest import TestLoader, TextTestRunner
+from pathlib import Path
 from test.easyblocks.module import cleanup
 
 import easybuild.tools.options as eboptions
 import easybuild.easyblocks.generic.pythonpackage as pythonpackage
+import easybuild.easyblocks.generic.cargo as cargo
 import easybuild.easyblocks.l.lammps as lammps
 import easybuild.easyblocks.p.python as python
 from easybuild.base.testing import TestCase
@@ -323,6 +325,92 @@ def test_det_py_install_scheme(self):
         res = pythonpackage.det_py_install_scheme()
         self.assertTrue(isinstance(res, str))
 
+    def test_cargo_toml_parsers(self):
+        """Test get_workspace_members in cargo easyblock"""
+        crate_dir = Path(tempfile.mkdtemp())
+        cargo_toml = crate_dir / 'Cargo.toml'
+
+        # Simple crate
+        write_file(cargo_toml, textwrap.dedent("""
+            [package]
+            name = "my_crate"
+            version = "0.1.0"
+            edition = "2021"
+            description = '''Line 1
+            Line 2
+            '''
+            readme = \"""README.md\"""
+            authors = [
+                '''Name d'Or Si''',
+            ]
+        """))
+        parsed = cargo.parse_toml(cargo_toml)
+        self.assertEqual(parsed, {
+            'package': {
+                'name': '"my_crate"',
+                'version': '"0.1.0"',
+                'edition': '"2021"',
+                'description': "'''Line 1\nLine 2\n'''",
+                'readme': '"""README.md"""',
+                'authors': "[\n'''Name d'Or Si''',\n]",
+            }
+        })
+        has_package, members = cargo.get_workspace_members(crate_dir)
+        self.assertTrue(has_package)
+        self.assertIsNone(members)
+
+        # Virtual manifest
+        write_file(cargo_toml, textwrap.dedent("""
+            [workspace]
+            members = [
+                "reqwest-middleware",
+                "reqwest-tracing",
+                "reqwest-retry",
+            ]
+        """))
+        parsed = cargo.parse_toml(cargo_toml)
+        self.assertEqual(parsed, {
+            'workspace': {
+                'members': '[\n"reqwest-middleware",\n"reqwest-tracing",\n"reqwest-retry",\n]',
+            }
+        })
+        has_package, members = cargo.get_workspace_members(crate_dir)
+        self.assertFalse(has_package)
+        self.assertEqual(members, ["reqwest-middleware", "reqwest-tracing", "reqwest-retry"])
+
+        # Workspace (root is a package too)
+        write_file(cargo_toml, textwrap.dedent("""
+            [package]
+            name = "nothing-linux-ui"
+            version = "0.0.2"
+            edition = "2021"
+            authors = ["sn99"]
+
+            [workspace]
+            members = ["nothing", "src-tauri"]
+
+            [dependencies]
+            leptos = { version = "0.6", features = ["csr"] }
+        """))
+        parsed = cargo.parse_toml(cargo_toml)
+        self.assertEqual(parsed, {
+            'package': {
+                "name": '"nothing-linux-ui"',
+                "version": '"0.0.2"',
+                "edition": '"2021"',
+                "authors": '["sn99"]',
+            },
+            'workspace': {
+                "members": '["nothing", "src-tauri"]',
+            },
+            'dependencies': {
+                "leptos": '{ version = "0.6", features = ["csr"] }',
+            },
+        })
+        has_package, members = cargo.get_workspace_members(crate_dir)
+        self.assertTrue(has_package)
+        self.assertEqual(members, ["nothing", "src-tauri"])
+
     def test_handle_local_py_install_scheme(self):
         """Test handle_local_py_install_scheme function provided by PythonPackage easyblock."""
 

From d57b376c7ac6b70f6f51751232109ed646afeac7 Mon Sep 17 00:00:00 2001
From: Alexander Grund <alexander.grund@tu-dresden.de>
Date: Wed, 12 Nov 2025 15:34:19 +0100
Subject: [PATCH 2/6] Accept parsed TOML file in get_workspace_members

Allow reusing the parsed result.
---
 easybuild/easyblocks/generic/cargo.py | 14 ++++++--------
 test/easyblocks/easyblock_specific.py |  8 ++++----
 2 files changed, 10 insertions(+), 12 deletions(-)

diff --git a/easybuild/easyblocks/generic/cargo.py b/easybuild/easyblocks/generic/cargo.py
index f6669804d04..c105f1516fd 100755
--- a/easybuild/easyblocks/generic/cargo.py
+++ b/easybuild/easyblocks/generic/cargo.py
@@ -161,17 +161,13 @@ def parse_toml(file: Path) -> Dict[str, str]:
     return result
 
 
-def get_workspace_members(crate_dir: Path):
-    """Find all members of a cargo workspace in crate_dir.
-
-    (Minimally) parse the Cargo.toml file.
+def get_workspace_members(cargo_toml: Dict[str, str]):
+    """Find all members of a cargo workspace in the parsed the Cargo.toml file.
 
     Return a tuple: (has_package, workspace-members).
     has_package determines if it is a virtual workspace ([workspace] and no [package])
     workspace-members are all members (subfolder names) if it is a workspace, otherwise None
     """
-    cargo_toml = parse_toml(crate_dir / 'Cargo.toml')
-
     # A virtual (workspace) manifest has no [package], but only a [workspace] section.
     has_package = 'package' in cargo_toml
 
@@ -422,7 +418,8 @@ def _setup_offline_config(self, git_sources):
         tmp_dir = Path(tempfile.mkdtemp(dir=self.builddir, prefix='tmp_crate_'))
         # Add checksum file for each crate such that it is recognized by cargo.
         # Glob to catch multiple folders in a source archive.
-        for crate_dir in (p.parent for p in Path(self.vendor_dir).glob('*/Cargo.toml')):
+        for cargo_toml in Path(self.vendor_dir).glob('*/Cargo.toml'):
+            crate_dir = cargo_toml.parent
             src = path_to_source.get(str(crate_dir))
             if src:
                 try:
@@ -440,7 +437,8 @@ def _setup_offline_config(self, git_sources):
             # otherwise (Only "[workspace]" section and no "[package]" section)
             # we have to remove the top-level folder or cargo fails with:
             # "found a virtual manifest at [...]Cargo.toml instead of a package manifest"
-            has_package, members = get_workspace_members(crate_dir)
+            parsed_toml = parse_toml(cargo_toml)
+            has_package, members = get_workspace_members(parsed_toml)
             if members:
                 self.log.info(f'Found workspace in {crate_dir}. Members: ' + ', '.join(members))
                 if not any((crate_dir / crate).is_dir() for crate in members):
diff --git a/test/easyblocks/easyblock_specific.py b/test/easyblocks/easyblock_specific.py
index 9f03ec6d073..953eb52b320 100644
--- a/test/easyblocks/easyblock_specific.py
+++ b/test/easyblocks/easyblock_specific.py
@@ -326,7 +326,7 @@ def test_det_py_install_scheme(self):
         self.assertTrue(isinstance(res, str))
 
     def test_cargo_toml_parsers(self):
-        """Test get_workspace_members in cargo easyblock"""
+        """Test get_workspace_members in the Cargo easyblock"""
         crate_dir = Path(tempfile.mkdtemp())
         cargo_toml = crate_dir / 'Cargo.toml'
 
@@ -355,7 +355,7 @@ def test_cargo_toml_parsers(self):
                 'authors': "[\n'''Name d'Or Si''',\n]",
             }
         })
-        has_package, members = cargo.get_workspace_members(crate_dir)
+        has_package, members = cargo.get_workspace_members(parsed)
         self.assertTrue(has_package)
         self.assertIsNone(members)
 
@@ -374,7 +374,7 @@ def test_cargo_toml_parsers(self):
                 'members': '[\n"reqwest-middleware",\n"reqwest-tracing",\n"reqwest-retry",\n]',
             }
         })
-        has_package, members = cargo.get_workspace_members(crate_dir)
+        has_package, members = cargo.get_workspace_members(parsed)
         self.assertFalse(has_package)
         self.assertEqual(members, ["reqwest-middleware", "reqwest-tracing", "reqwest-retry"])
 
@@ -407,7 +407,7 @@ def test_cargo_toml_parsers(self):
                 "leptos": '{ version = "0.6", features = ["csr"] }',
             },
         })
-        has_package, members = cargo.get_workspace_members(crate_dir)
+        has_package, members = cargo.get_workspace_members(parsed)
         self.assertTrue(has_package)
         self.assertEqual(members, ["nothing", "src-tauri"])
 

From 0a86a056d86cfcc4833d02e85f4861836c3bc4d6 Mon Sep 17 00:00:00 2001
From: Alexander Grund <alexander.grund@tu-dresden.de>
Date: Wed, 12 Nov 2025 15:51:48 +0100
Subject: [PATCH 3/6] Correctly handle multiline strings

When there is a line
> key = """

the value starts and ends with the delimitter wrongly terminating the
value parser.
Check that there is anything else first.
---
 easybuild/easyblocks/generic/cargo.py |  7 ++++---
 test/easyblocks/easyblock_specific.py | 15 +++++++++++----
 2 files changed, 15 insertions(+), 7 deletions(-)

diff --git a/easybuild/easyblocks/generic/cargo.py b/easybuild/easyblocks/generic/cargo.py
index c105f1516fd..56eeff26472 100755
--- a/easybuild/easyblocks/generic/cargo.py
+++ b/easybuild/easyblocks/generic/cargo.py
@@ -128,8 +128,9 @@ def parse_toml(file: Path) -> Dict[str, str]:
     expected_end = None
     current_section = None
     content = read_file(file)
+    num = raw_line = None
     try:
-        for raw_line in content.splitlines():
+        for num, raw_line in enumerate(content.splitlines()):
             line: str = raw_line.split("#", 1)[0].strip()
             if not line:
                 continue
@@ -153,11 +154,11 @@ def parse_toml(file: Path) -> Dict[str, str]:
                     expected_end = None
             else:
                 pending_value += '\n' + line
-            if expected_end is None or pending_value.endswith(expected_end):
+            if expected_end is None or (pending_value != expected_end and pending_value.endswith(expected_end)):
                 result[current_section][pending_key] = pending_value.strip()
                 pending_key = None
     except Exception as e:
-        raise ValueError(f'Failed to parse {file} ({content}): {e}')
+        raise ValueError(f'Failed to parse {file}, error {e} at line {num}: {raw_line}')
     return result
 
 
diff --git a/test/easyblocks/easyblock_specific.py b/test/easyblocks/easyblock_specific.py
index 953eb52b320..31f72783aa2 100644
--- a/test/easyblocks/easyblock_specific.py
+++ b/test/easyblocks/easyblock_specific.py
@@ -336,13 +336,18 @@ def test_cargo_toml_parsers(self):
             name = "my_crate"
             version = "0.1.0"
             edition = "2021"
-            description = '''Line 1
+            description = '''
+            Line 1
             Line 2
             '''
-            readme = \"""README.md\"""
+            readme = \"""
+            README.md
+            \"""
+            license = \"""MIT\"""
             authors = [
                 '''Name d'Or Si''',
             ]
+            empty=''''''
         """))
         parsed = cargo.parse_toml(cargo_toml)
         self.assertEqual(parsed, {
@@ -350,9 +355,11 @@ def test_cargo_toml_parsers(self):
                 'name': '"my_crate"',
                 'version': '"0.1.0"',
                 'edition': '"2021"',
-                'description': "'''Line 1\nLine 2\n'''",
-                'readme': '"""README.md"""',
+                'description': "'''\nLine 1\nLine 2\n'''",
+                'readme': '"""\nREADME.md\n"""',
+                'license': '"""MIT"""',
                 'authors': "[\n'''Name d'Or Si''',\n]",
+                'empty': "''''''",
             }
         })
         has_package, members = cargo.get_workspace_members(parsed)

From e8fcd046a5fcc2c9e409d748d1dd82758246b03e Mon Sep 17 00:00:00 2001
From: Alexander Grund <alexander.grund@tu-dresden.de>
Date: Wed, 12 Nov 2025 17:04:41 +0100
Subject: [PATCH 4/6] Make comment handling more resilient

'#'-signs can be embedded in strings
---
 easybuild/easyblocks/generic/cargo.py | 56 ++++++++++++++++++++++-----
 test/easyblocks/easyblock_specific.py | 13 ++++---
 2 files changed, 55 insertions(+), 14 deletions(-)

diff --git a/easybuild/easyblocks/generic/cargo.py b/easybuild/easyblocks/generic/cargo.py
index 56eeff26472..96540ead760 100755
--- a/easybuild/easyblocks/generic/cargo.py
+++ b/easybuild/easyblocks/generic/cargo.py
@@ -117,6 +117,42 @@ def parse_toml_list(value: str) -> List[str]:
     return result
 
 
+def _clean_line(line: str, expected_end: Union[str, None]) -> str:
+    """Remove comments and trim line"""
+    if '#' not in line:
+        return line.strip()
+    if expected_end is not None and expected_end[0] in ("'", '"'):
+        try:
+            idx = line.index(expected_end) + len(expected_end)
+        except ValueError:
+            return line.strip()  # Ignore #-sign in multi-line string
+    else:
+        idx = 0
+    in_str = False
+    escaped = False
+    while idx < len(line):
+        c = line[idx]
+        if in_str:
+            if escaped:
+                if c == '\\':
+                    escaped = False
+            elif c == '"':
+                in_str = False
+            elif c == '\\':
+                escaped = True
+        elif c == '#':
+            break
+        elif c == '"':
+            in_str = True
+        elif c == "'":
+            try:
+                idx = line.index("'", idx + 1)
+            except ValueError:
+                idx = len(line)
+        idx += 1
+    return line[:idx].strip()
+
+
 def parse_toml(file: Path) -> Dict[str, str]:
     """Minimally parse a TOML file into sections, keys and values
 
@@ -129,9 +165,15 @@ def parse_toml(file: Path) -> Dict[str, str]:
     current_section = None
     content = read_file(file)
     num = raw_line = None
+    start_end = {
+        '[': ']',
+        '{': '}',
+        '"""': '"""',
+        "'''": "'''",
+    }
     try:
         for num, raw_line in enumerate(content.splitlines()):
-            line: str = raw_line.split("#", 1)[0].strip()
+            line: str = _clean_line(raw_line, expected_end)
             if not line:
                 continue
             if pending_key is None and line.startswith("[") and line.endswith("]"):
@@ -142,14 +184,10 @@ def parse_toml(file: Path) -> Dict[str, str]:
                 key, val = line.split("=", 1)
                 pending_key = key.strip()
                 pending_value = val.strip()
-                if pending_value.startswith('['):
-                    expected_end = ']'
-                elif pending_value.startswith('{'):
-                    expected_end = '}'
-                elif pending_value.startswith('"""'):
-                    expected_end = '"""'
-                elif pending_value.startswith("'''"):
-                    expected_end = "'''"
+                for start, end in start_end.items():
+                    if pending_value.startswith(start):
+                        expected_end = end
+                        break
                 else:
                     expected_end = None
             else:
diff --git a/test/easyblocks/easyblock_specific.py b/test/easyblocks/easyblock_specific.py
index 31f72783aa2..5875ccac916 100644
--- a/test/easyblocks/easyblock_specific.py
+++ b/test/easyblocks/easyblock_specific.py
@@ -329,17 +329,19 @@ def test_cargo_toml_parsers(self):
         """Test get_workspace_members in the Cargo easyblock"""
         crate_dir = Path(tempfile.mkdtemp())
         cargo_toml = crate_dir / 'Cargo.toml'
-
         # Simple crate
         write_file(cargo_toml, textwrap.dedent("""
             [package]
-            name = "my_crate"
+            #[dummy]
+            # ignore = this
+            name = 'my_crate\\' #comment1' # comment2
             version = "0.1.0"
-            edition = "2021"
+            edition = "2021#2"
             description = '''
             Line 1
             Line 2
             '''
+            documentation = "url?\\"#anchor"
             readme = \"""
             README.md
             \"""
@@ -352,10 +354,11 @@ def test_cargo_toml_parsers(self):
         parsed = cargo.parse_toml(cargo_toml)
         self.assertEqual(parsed, {
             'package': {
-                'name': '"my_crate"',
+                'name': "'my_crate\\'",
                 'version': '"0.1.0"',
-                'edition': '"2021"',
+                'edition': '"2021#2"',
                 'description': "'''\nLine 1\nLine 2\n'''",
+                'documentation': '"url?\\"#anchor"',
                 'readme': '"""\nREADME.md\n"""',
                 'license': '"""MIT"""',
                 'authors': "[\n'''Name d'Or Si''',\n]",

From fb11ab353c0447e27d829b9a7a7bdd102685bca7 Mon Sep 17 00:00:00 2001
From: Alexander Grund <alexander.grund@tu-dresden.de>
Date: Thu, 13 Nov 2025 09:29:30 +0100
Subject: [PATCH 5/6] Implement merging Cargo.toml file with workspace file

Resolve backreferences like `authors.workspace = true`
---
 easybuild/easyblocks/generic/cargo.py | 37 +++++++++++++++--
 test/easyblocks/easyblock_specific.py | 58 ++++++++++++++++++++++++++-
 2 files changed, 91 insertions(+), 4 deletions(-)

diff --git a/easybuild/easyblocks/generic/cargo.py b/easybuild/easyblocks/generic/cargo.py
index 96540ead760..31b82daa822 100755
--- a/easybuild/easyblocks/generic/cargo.py
+++ b/easybuild/easyblocks/generic/cargo.py
@@ -153,7 +153,7 @@ def _clean_line(line: str, expected_end: Union[str, None]) -> str:
     return line[:idx].strip()
 
 
-def parse_toml(file: Path) -> Dict[str, str]:
+def parse_toml(file_or_content: Union[Path, str]) -> Dict[str, str]:
     """Minimally parse a TOML file into sections, keys and values
 
     Values will be the raw strings (including quotes for string-typed values)"""
@@ -163,7 +163,7 @@ def parse_toml(file: Path) -> Dict[str, str]:
     pending_value = None
     expected_end = None
     current_section = None
-    content = read_file(file)
+    content = read_file(file_or_content) if isinstance(file_or_content, Path) else file_or_content
     num = raw_line = None
     start_end = {
         '[': ']',
@@ -196,7 +196,7 @@ def parse_toml(file: Path) -> Dict[str, str]:
                 result[current_section][pending_key] = pending_value.strip()
                 pending_key = None
     except Exception as e:
-        raise ValueError(f'Failed to parse {file}, error {e} at line {num}: {raw_line}')
+        raise ValueError(f'Failed to parse {file_or_content}, error {e} at line {num}: {raw_line}')
     return result
 
 
@@ -236,6 +236,35 @@ def get_workspace_members(cargo_toml: Dict[str, str]):
     return has_package, members
 
 
+def merge_sub_crate(cargo_toml_path: Path, workspace_toml: Dict[str, str]):
+    """Resolve workspace references in the Cargo.toml file"""
+    # Lines such as 'authors.workspace = true' must be replaced by 'authors = <value from workspace.package>'
+    content: str = read_file(cargo_toml_path)
+    SUFFIX = '.workspace'
+    if SUFFIX not in content:
+        return
+    cargo_toml = parse_toml(content)
+    lines = content.splitlines()
+
+    def do_replacement(section, workspace_section):
+        if not section or not workspace_section:
+            return
+
+        for key, value in section.items():
+            if key.endswith(SUFFIX) and value == 'true':
+                real_key = key[:-len(SUFFIX)]
+                value = workspace_section[real_key]
+                idx = next(idx for idx, line in enumerate(lines) if key in line)
+                lines[idx] = f'{real_key} = {value}'
+
+    do_replacement(cargo_toml.get('package'), workspace_toml.get('workspace.package'))
+    do_replacement(cargo_toml.get('dependencies'), workspace_toml.get('workspace.dependencies'))
+    do_replacement(cargo_toml.get('build-dependencies'), workspace_toml.get('workspace.dependencies'))
+    do_replacement(cargo_toml.get('dev-dependencies'), workspace_toml.get('workspace.dependencies'))
+
+    write_file(cargo_toml_path, '\n'.join(lines))
+
+
 def get_checksum(src, log):
     """Get the checksum from an extracted source"""
     checksum = src['checksum']
@@ -502,6 +531,8 @@ def _setup_offline_config(self, git_sources):
                         # Use copy_dir to resolve symlinks that might point to the parent folder
                         copy_dir(tmp_crate_dir / member, target_path, symlinks=False)
                         cargo_pkg_dirs.append(target_path)
+                        self.log.info(f'Resolving workspace values for crate {member}')
+                        merge_sub_crate(target_path / 'Cargo.toml', parsed_toml)
                     if has_package:
                         # Remove the copied crate folders
                         for member in members:
diff --git a/test/easyblocks/easyblock_specific.py b/test/easyblocks/easyblock_specific.py
index 5875ccac916..e4ee2c066fd 100644
--- a/test/easyblocks/easyblock_specific.py
+++ b/test/easyblocks/easyblock_specific.py
@@ -53,7 +53,7 @@
 from easybuild.tools.build_log import EasyBuildError
 from easybuild.tools.config import GENERAL_CLASS, get_module_syntax
 from easybuild.tools.environment import modify_env
-from easybuild.tools.filetools import adjust_permissions, mkdir, move_file, remove_dir, symlink, write_file
+from easybuild.tools.filetools import adjust_permissions, mkdir, move_file, read_file, remove_dir, symlink, write_file
 from easybuild.tools.modules import modules_tool
 from easybuild.tools.options import set_tmpdir
 from easybuild.tools.run import RunShellCmdResult
@@ -421,6 +421,62 @@ def test_cargo_toml_parsers(self):
         self.assertTrue(has_package)
         self.assertEqual(members, ["nothing", "src-tauri"])
 
+    def test_cargo_merge_sub_crate(self):
+        """Test merge_sub_crate in the Cargo easyblock"""
+        crate_dir = Path(tempfile.mkdtemp())
+        cargo_toml = crate_dir / 'Cargo.toml'
+        write_file(cargo_toml, textwrap.dedent("""
+            [workspace]
+            members = ["bar"]
+
+            [workspace.package]
+            version = "1.2.3"
+            authors = ["Nice Folks"]
+            description = "A short description of my package"
+            documentation = "https://example.com/bar"
+
+            [workspace.dependencies]
+            regex = { version = "1.6.0", default-features = false, features = ["std"] }
+            cc = "1.0.73"
+            rand = "0.8.5"
+        """))
+        ws_parsed = cargo.parse_toml(cargo_toml)
+        write_file(cargo_toml, textwrap.dedent("""
+            [package]
+            name = "bar"
+            version.workspace = true
+            authors.workspace = true
+            description.workspace = true
+            documentation.workspace = true
+
+            [dependencies]
+            regex.workspace = true
+
+            [build-dependencies]
+            cc.workspace = true
+
+            [dev-dependencies]
+            rand.workspace = true
+        """))
+        cargo.merge_sub_crate(cargo_toml, ws_parsed)
+        self.assertEqual(read_file(cargo_toml).strip(), textwrap.dedent("""
+            [package]
+            name = "bar"
+            version = "1.2.3"
+            authors = ["Nice Folks"]
+            description = "A short description of my package"
+            documentation = "https://example.com/bar"
+
+            [dependencies]
+            regex = { version = "1.6.0", default-features = false, features = ["std"] }
+
+            [build-dependencies]
+            cc = "1.0.73"
+
+            [dev-dependencies]
+            rand = "0.8.5"
+        """).strip())
+
     def test_handle_local_py_install_scheme(self):
         """Test handle_local_py_install_scheme function provided by PythonPackage easyblock."""
 

From 50602d7fe1878811fd52e9908eb87a7297d3a754 Mon Sep 17 00:00:00 2001
From: Alexander Grund <alexander.grund@tu-dresden.de>
Date: Thu, 13 Nov 2025 10:33:05 +0100
Subject: [PATCH 6/6] Avoid B007 hound warning

We use the line number only outside the loop which triggers
> Loop control variable 'num' not used within the loop body. If this is intended, start the name with an underscore.
---
 easybuild/easyblocks/generic/cargo.py | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/easybuild/easyblocks/generic/cargo.py b/easybuild/easyblocks/generic/cargo.py
index 31b82daa822..fd190ba96bc 100755
--- a/easybuild/easyblocks/generic/cargo.py
+++ b/easybuild/easyblocks/generic/cargo.py
@@ -164,7 +164,7 @@ def parse_toml(file_or_content: Union[Path, str]) -> Dict[str, str]:
     expected_end = None
     current_section = None
     content = read_file(file_or_content) if isinstance(file_or_content, Path) else file_or_content
-    num = raw_line = None
+    line_num = raw_line = None
     start_end = {
         '[': ']',
         '{': '}',
@@ -172,7 +172,7 @@ def parse_toml(file_or_content: Union[Path, str]) -> Dict[str, str]:
         "'''": "'''",
     }
     try:
-        for num, raw_line in enumerate(content.splitlines()):
+        for line_num, raw_line in enumerate(content.splitlines()): # noqa B007: line_num used in error only
             line: str = _clean_line(raw_line, expected_end)
             if not line:
                 continue
@@ -196,7 +196,7 @@ def parse_toml(file_or_content: Union[Path, str]) -> Dict[str, str]:
                 result[current_section][pending_key] = pending_value.strip()
                 pending_key = None
     except Exception as e:
-        raise ValueError(f'Failed to parse {file_or_content}, error {e} at line {num}: {raw_line}')
+        raise ValueError(f'Failed to parse {file_or_content}, error {e} at line {line_num}: {raw_line}')
     return result