Switch crypto_data_tests.py to automatic dependencies

In `psa_test_cases.TestCase`:

* Implement basic support for automatic dependencies, by calling
  `psa_information.automatic_dependencies`.
* Support an alternative dependency prefix.

No changes to the generated file.

Signed-off-by: Gilles Peskine <[email protected]>

scripts/mbedtls_framework/crypto_data_tests.py

@@ -16,15 +16,6 @@ from . import psa_test_case
 from . import test_case
 
 
-def psa_low_level_dependencies(*expressions: str) -> List[str]:
-    """Infer dependencies of a PSA low-level test case by looking for PSA_xxx symbols.
-
-    This function generates MBEDTLS_PSA_BUILTIN_xxx symbols.
-    """
-    return psa_information.automatic_dependencies(*expressions,
-                                                  prefix='MBEDTLS_PSA_BUILTIN_')
-
-
 class HashPSALowLevel:
     """Generate test cases for the PSA low-level hash interface."""
 
@@ -68,7 +59,7 @@ class HashPSALowLevel:
                       function: str, note: str,
                       arguments: List[str]) -> test_case.TestCase:
         """Construct one test case involving a hash."""
-        tc = psa_test_case.TestCase()
+        tc = psa_test_case.TestCase(dependency_prefix='MBEDTLS_PSA_BUILTIN_')
         tc.set_description('{}{} {}'
                            .format(function,
                                    ' ' + note if note else '',
@@ -76,7 +67,6 @@ class HashPSALowLevel:
         tc.set_function(function)
         tc.set_arguments([alg.expression] +
                          ['"{}"'.format(arg) for arg in arguments])
-        tc.set_dependencies(psa_low_level_dependencies(alg.expression))
         return tc
 
     def test_cases_for_hash(self,

scripts/mbedtls_framework/psa_test_case.py

@@ -9,6 +9,7 @@ import os
 import re
 from typing import FrozenSet, List, Optional, Set
 
+from . import psa_information
 from . import test_case
 
 
@@ -57,16 +58,24 @@ class TestCase(test_case.TestCase):
     involved in a given test case.
     """
 
-    def __init__(self) -> None:
+    def __init__(self, dependency_prefix: Optional[str] = None) -> None:
+        """Construct a test case for a PSA Crypto API call.
+
+        `dependency_prefix`: prefix to use in dependencies. Defaults to
+                             ``'PSA_WANT_'``. Use ``'MBEDTLS_PSA_BUILTIN_'``
+                             when specifically testing builtin implementations.
+        """
         super().__init__()
         del self.dependencies
         self.manual_dependencies = [] #type: List[str]
         self.automatic_dependencies = set() #type: Set[str]
+        self.dependency_prefix = dependency_prefix #type: Optional[str]
 
-    @staticmethod
-    def infer_dependencies(_arguments: List[str]) -> List[str]:
+    def infer_dependencies(self, arguments: List[str]) -> List[str]:
         """Infer dependencies based on the test case arguments."""
-        return [] # not implemented yet
+        dependencies = psa_information.automatic_dependencies(*arguments,
+                                                              prefix=self.dependency_prefix)
+        return dependencies
 
     def set_arguments(self, arguments: List[str]) -> None:
         """Set test case arguments and automatically infer dependencies."""