Restore deleted deviations suppression query

change_notes/2025-03-26-deviations-suppression.md

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+ - The `DeviationsSuppression.ql` query has been restored after being incorrectly deleted in a previous release.

cpp/common/src/codingstandards/cpp/deviations/DeviationsSuppression.qhelp

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+<!DOCTYPE qhelp PUBLIC "-//Semmle//qhelp//EN" "qhelp.dtd">
+<qhelp>
+    <overview>
+        <p>This query generates suppression information for rules that have an associated deviation record.</p>
+    </overview>
+    <references>
+        <li>
+            MISRA Compliance 2020 document:
+            <a href="https://www.misra.org.uk/app/uploads/2021/06/MISRA-Compliance-2020.pdf">Chapter 4.2 (page 12) - Deviations.</a>
+        </li>
+    </references>
+</qhelp>

cpp/common/src/codingstandards/cpp/deviations/DeviationsSuppression.ql

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+/**
+ * @name Deviation suppression
+ * @description Generates information about files and locations where certain alerts should be considered suppressed by deviations.
+ * @kind alert-suppression
+ * @id cpp/coding-standards/deviation-suppression
+ */
+
+import cpp
+import Deviations
+
+/** Holds if `lineNumber` is an indexed line number in file `f`. */
+private predicate isLineNumber(File f, int lineNumber) {
+  exists(Location l | l.getFile() = f |
+    l.getStartLine() = lineNumber
+    or
+    l.getEndLine() = lineNumber
+  )
+}
+
+/** Gets the last line number in `f`. */
+private int getLastLineNumber(File f) { result = max(int lineNumber | isLineNumber(f, lineNumber)) }
+
+/** Gets the last column number on the last line of `f`. */
+int getLastColumnNumber(File f) {
+  result =
+    max(Location l |
+      l.getFile() = f and
+      l.getEndLine() = getLastLineNumber(f)
+    |
+      l.getEndColumn()
+    )
+}
+
+newtype TDeviationScope =
+  TDeviationRecordFileScope(DeviationRecord dr, File file) {
+    exists(string deviationPath |
+      dr.isDeviated(_, deviationPath) and
+      file.getRelativePath().prefix(deviationPath.length()) = deviationPath
+    )
+  } or
+  TDeviationRecordCommentScope(DeviationRecord dr, Comment c) { c = dr.getACodeIdentifierComment() }
+
+/** A deviation scope. */
+class DeviationScope extends TDeviationScope {
+  /** Gets the location at which this deviation was defined. */
+  abstract Locatable getDeviationDefinitionLocation();
+
+  /** Gets the Query being deviated. */
+  abstract Query getQuery();
+
+  abstract string toString();
+
+  abstract predicate hasLocationInfo(
+    string filepath, int startline, int startcolumn, int endline, int endcolumn
+  );
+}
+
+/** A deviation scope derived from a "path" entry in a `DeviationRecord`. */
+class DeviationRecordFileScope extends DeviationScope, TDeviationRecordFileScope {
+  private DeviationRecord getDeviationRecord() { this = TDeviationRecordFileScope(result, _) }
+
+  override Locatable getDeviationDefinitionLocation() { result = getDeviationRecord() }
+
+  private File getFile() { this = TDeviationRecordFileScope(_, result) }
+
+  override Query getQuery() { result = getDeviationRecord().getQuery() }
+
+  override predicate hasLocationInfo(
+    string filepath, int startline, int startcolumn, int endline, int endcolumn
+  ) {
+    // In an ideal world, we would produce a URL here that informed the AlertSuppression code that
+    // the whole file was suppressed. However, experimentation suggestions the alert suppression
+    // code only works with locations with lines and columns, so we generate a location that covers
+    // the whole "indexed" file, by finding the location indexed in the database with the latest
+    // line and column number.
+    exists(File f | f = getFile() |
+      f.getLocation().hasLocationInfo(filepath, _, _, _, _) and
+      startline = 1 and
+      startcolumn = 1 and
+      endline = getLastLineNumber(f) and
+      endcolumn = getLastColumnNumber(f)
+    )
+  }
+
+  override string toString() {
+    result = "Deviation of " + getDeviationRecord().getQuery() + " for " + getFile() + "."
+  }
+}
+
+/**
+ * A deviation scope derived from a comment corresponding to a "code-identifier" entry for a
+ * `DeviationRecord`.
+ */
+class DeviationRecordCommentScope extends DeviationScope, TDeviationRecordCommentScope {
+  private DeviationRecord getDeviationRecord() { this = TDeviationRecordCommentScope(result, _) }
+
+  private Comment getComment() { this = TDeviationRecordCommentScope(_, result) }
+
+  override Locatable getDeviationDefinitionLocation() { result = getDeviationRecord() }
+
+  override Query getQuery() { result = getDeviationRecord().getQuery() }
+
+  override predicate hasLocationInfo(
+    string filepath, int startline, int startcolumn, int endline, int endcolumn
+  ) {
+    getComment().getLocation().hasLocationInfo(filepath, startline, _, endline, endcolumn) and
+    startcolumn = 1
+  }
+
+  override string toString() {
+    result =
+      "Deviation of " + getDeviationRecord().getQuery() + " for comment " + getComment() + "."
+  }
+}
+
+from DeviationScope deviationScope
+select deviationScope.getDeviationDefinitionLocation(), // suppression comment
+  "// lgtm[" + deviationScope.getQuery().getQueryId() + "]", // text of suppression comment (excluding delimiters)
+  "lgtm[" + deviationScope.getQuery().getQueryId() + "]", // text of suppression annotation
+  deviationScope // scope of suppression

cpp/common/test/deviations/deviations_report_deviated/DeviationsSuppression.expected

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+| file://:0:0:0:0 | (no string representation) | // lgtm[cpp/autosar/type-long-double-used] | lgtm[cpp/autosar/type-long-double-used] | main.cpp:12:1:12:58 | Deviation of cpp/autosar/type-long-double-used for comment // a-0-4-2-deviation COMPLIANT[DEVIATED]. |
+| file://:0:0:0:0 | (no string representation) | // lgtm[cpp/autosar/unused-return-value] | lgtm[cpp/autosar/unused-return-value] | nested/nested2/test2.h:1:1:6:1 | Deviation of cpp/autosar/unused-return-value for nested/nested2/test2.h. |
+| file://:0:0:0:0 | (no string representation) | // lgtm[cpp/autosar/useless-assignment] | lgtm[cpp/autosar/useless-assignment] | coding-standards.xml:1:1:17:19 | Deviation of cpp/autosar/useless-assignment for coding-standards.xml. |
+| file://:0:0:0:0 | (no string representation) | // lgtm[cpp/autosar/useless-assignment] | lgtm[cpp/autosar/useless-assignment] | main.cpp:1:1:14:1 | Deviation of cpp/autosar/useless-assignment for main.cpp. |
+| file://:0:0:0:0 | (no string representation) | // lgtm[cpp/autosar/useless-assignment] | lgtm[cpp/autosar/useless-assignment] | nested/coding-standards.xml:1:1:13:19 | Deviation of cpp/autosar/useless-assignment for nested/coding-standards.xml. |
+| file://:0:0:0:0 | (no string representation) | // lgtm[cpp/autosar/useless-assignment] | lgtm[cpp/autosar/useless-assignment] | nested/nested2/test2.h:1:1:6:1 | Deviation of cpp/autosar/useless-assignment for nested/nested2/test2.h. |
+| file://:0:0:0:0 | (no string representation) | // lgtm[cpp/autosar/useless-assignment] | lgtm[cpp/autosar/useless-assignment] | nested/test.h:1:1:6:1 | Deviation of cpp/autosar/useless-assignment for nested/test.h. |

cpp/common/test/deviations/deviations_report_deviated/DeviationsSuppression.qlref

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+codingstandards/cpp/deviations/DeviationsSuppression.ql