refactor: Remove outdated (and unused) default repo_top argument

This code was based on dvsim living inside the OpenTitan repository.
Fortunately, it is never used: we always pass a third argument to
_parse_testplan.

Also, fail more understandably if there is an hjson parse error or an
invalid filename passed to _parse_hjson.

Finally, simplify the Testplan constructor so that it always expects a
name for its testplan (rather than exiting the program silently if
there isn't one).

We also change that argument to explicitly have type str (as opposed
to Path) and explain why: the string can have suffix values that
filter the set of tests.

Signed-off-by: Rupert Swarbrick <rswarbrick@lowrisc.org>

Author: rswarbrick

src/dvsim/sim/flow.py

@@ -330,7 +330,9 @@ def _create_objects(self) -> None:
             self.regressions.extend(self.testplan.get_stage_regressions())
         else:
             # Create a dummy testplan with no entries.
-            self.testplan = Testplan(None, name=self.name)
+            self.testplan = Testplan(
+                "<dummy testplan>", repo_top=Path(self.proj_root), name=self.name
+            )
 
         # Create regressions
         self.regressions = Regression.create_regressions(self.regressions, self, self.tests)

src/dvsim/testplan.py

@@ -4,12 +4,11 @@
 
 """Testpoint and Testplan classes for maintaining the testplan."""
 
-import os
 import re
 import sys
 from collections import defaultdict
 from pathlib import Path
-from typing import TextIO
+from typing import Any, TextIO
 
 import hjson
 from tabulate import tabulate
@@ -260,15 +259,9 @@ class Testplan:
     element_cls = {"testpoint": Testpoint, "covergroup": Covergroup}
 
     @staticmethod
-    def _parse_hjson(filename):
-        """Parses an input file with Hjson and returns a dict."""
-        try:
-            return hjson.load(Path(filename).open())
-        except OSError:
-            pass
-        except hjson.scanner.HjsonDecodeError:
-            pass
-        sys.exit(1)
+    def _parse_hjson(filename: Path) -> dict[str, Any]:
+        """Parse an Hjson file at the given path and return it as a dict."""
+        return hjson.loads(Path(filename).read_text(encoding="utf-8"))
 
     @staticmethod
     def _create_testplan_elements(kind: str, raw_dicts_list: list, tags: set) -> list[Element]:
@@ -311,36 +304,37 @@ def _get_percentage(value, total) -> str:
         perc = value / total * 100 * 1.0
         return f"{round(perc, 2):.2f} %"
 
-    def __init__(self, filename, repo_top=None, name=None) -> None:
+    def __init__(self, tagged_filename: str, repo_top: Path, name: str) -> None:
         """Initialize the testplan.
 
-        filename is the Hjson file that captures the testplan. It may be
-        suffixed with tags separated with a colon delimiter to filter the
-        testpoints. For example: path/too/foo_testplan.hjson:bar:baz
-        repo_top is an optional argument indicating the path to top level repo
-        / project directory. It is used with filename arg.
-        name is an optional argument indicating the name of the testplan / DUT.
-        It overrides the name set in the testplan Hjson.
+        Args:
+          tagged_filename: Describes the Hjson file that captures the testplan.
+                           This is a string, rather than a Path object, because
+                           it may be suffixed with tags separated with a colon
+                           delimiter to filter the testpoints.
+
+                           For example: "path/to/foo_testplan.hjson:bar:baz"
+
+          repo_top:        The path to the top level repo / project directory.
+                           This is combined with the filename argument.
+
+          name:            The name of the testplan / DUT. It overrides any
+                           name set in the testplan Hjson.
+
         """
-        self.name = None
+        self.name = name
         self.testpoints = []
         self.covergroups = []
         self.test_results_mapped = False
 
         # Split the filename into filename and tags, if provided.
-        split = str(filename).split(":")
+        split = tagged_filename.split(":")
         filename = Path(split[0])
         tags = set(split[1:])
 
         if filename.exists():
             self._parse_testplan(filename, tags, repo_top)
 
-        if name:
-            self.name = name
-
-        if not self.name:
-            sys.exit(1)
-
         # Represents current progress towards each stage. Stage = N.A.
         # is used to indicate the unmapped tests.
         self.progress = {}
@@ -402,7 +396,7 @@ def _get_imported_testplan_paths(
 
         return result
 
-    def _parse_testplan(self, filename: Path, tags: set, repo_top=None) -> None:
+    def _parse_testplan(self, filename: Path, tags: set[str], repo_top: Path) -> None:
         """Parse testplan Hjson file and create the testplan elements.
 
         It creates the list of testpoints and covergroups extracted from the
@@ -411,10 +405,6 @@ def _parse_testplan(self, filename: Path, tags: set, repo_top=None) -> None:
         filename is the path to the testplan file written in Hjson format.
         repo_top is an optional argument indicating the path to repo top.
         """
-        if repo_top is None:
-            # Assume dvsim's original location: $REPO_TOP/util/dvsim.
-            repo_top = Path(__file__).parent.parent.parent.resolve()
-
         obj = Testplan._parse_hjson(filename)
 
         parsed = set()
@@ -430,7 +420,7 @@ def _parse_testplan(self, filename: Path, tags: set, repo_top=None) -> None:
             if testplan in parsed:
                 sys.exit(1)
             parsed.add(testplan)
-            data = self._parse_hjson(os.path.join(repo_top, testplan))
+            data = self._parse_hjson(repo_top / testplan)
             imported_testplans.extend(
                 self._get_imported_testplan_paths(
                     testplan,
@@ -725,16 +715,16 @@ def get_test_results_summary(self):
         result["Pass Rate"] = self._get_percentage(tr.passing, tr.total)
         return result
 
-    def get_sim_results(self, sim_results_file, fmt="md"):
+    def get_sim_results(self, sim_results_file: str, fmt="md"):
         """Returns the mapped sim result tables in HTML formatted text.
 
-        The data extracted from the sim_results table HJson file is mapped into
+        The data extracted from the sim_results table Hjson file is mapped into
         a test results, test progress, covergroup progress and coverage tables.
 
         fmt is either 'md' (markdown) or 'html'.
         """
         assert fmt in ["md", "html"]
-        sim_results = Testplan._parse_hjson(sim_results_file)
+        sim_results = Testplan._parse_hjson(Path(sim_results_file))
         test_results_ = sim_results.get("test_results", None)
 
         test_results = []