From 11c842f4ef613bd2d92c7b5e8a6041260a706fb7 Mon Sep 17 00:00:00 2001
From: Claude <claude@anthropic.local>
Date: Fri, 24 Apr 2026 00:34:48 +0000
Subject: [PATCH 1/2] #841: Add failing tests for NPE when +unlint range
 references absent lint

Reproduces the NullPointerException thrown by DefectMissing.apply() when
a range-form unlint expression (name:line-line) references a lint name
that is not present in the defects map.
---
 .../org/eolang/lints/DefectMissingTest.java   | 19 ++++++++++++++++
 .../lints/LtUnlintNonExistingDefectTest.java  | 22 +++++++++++++++++++
 2 files changed, 41 insertions(+)

diff --git a/src/test/java/org/eolang/lints/DefectMissingTest.java b/src/test/java/org/eolang/lints/DefectMissingTest.java
index 25f89784f..fb412dffc 100644
--- a/src/test/java/org/eolang/lints/DefectMissingTest.java
+++ b/src/test/java/org/eolang/lints/DefectMissingTest.java
@@ -80,4 +80,23 @@ void returnsTrueIfSomeLineIsOutOfRange() {
             Matchers.equalTo(true)
         );
     }
+
+    @Test
+    void returnsTrueWhenRangeReferencesAbsentLint() {
+        MatcherAssert.assertThat(
+            "Defect should be missing when referenced lint is absent from map",
+            new DefectMissing(new MapOf<>("other-lint", new ListOf<>(1, 2)), new ListOf<>())
+                .apply("ascii-only:1-5"),
+            Matchers.equalTo(true)
+        );
+    }
+
+    @Test
+    void returnsTrueWhenRangeReferencesLintInEmptyMap() {
+        MatcherAssert.assertThat(
+            "Defect should be missing when defects map is empty",
+            new DefectMissing(new MapOf<>(), new ListOf<>()).apply("ascii-only:1-5"),
+            Matchers.equalTo(true)
+        );
+    }
 }
diff --git a/src/test/java/org/eolang/lints/LtUnlintNonExistingDefectTest.java b/src/test/java/org/eolang/lints/LtUnlintNonExistingDefectTest.java
index eca2a1deb..eb4b93e87 100644
--- a/src/test/java/org/eolang/lints/LtUnlintNonExistingDefectTest.java
+++ b/src/test/java/org/eolang/lints/LtUnlintNonExistingDefectTest.java
@@ -222,4 +222,26 @@ void catchesUnlintWithOutOfRangeLines() throws IOException {
             Matchers.iterableWithSize(1)
         );
     }
+
+    @Test
+    void catchesRangeUnlintOfAbsentLint() throws IOException {
+        MatcherAssert.assertThat(
+            "Range unlint referencing an absent lint should be reported, not throw NPE",
+            new LtUnlintNonExistingDefect(
+                new ListOf<>(new LtAsciiOnly()),
+                new ListOf<>()
+            ).defects(
+                new EoSyntax(
+                    String.join(
+                        "\n",
+                        "+unlint ascii-only:1-5",
+                        "",
+                        "# Hello.",
+                        "[] > main"
+                    )
+                ).parsed()
+            ),
+            Matchers.hasSize(Matchers.greaterThan(0))
+        );
+    }
 }

From 3f7fca2aaf1c7d283f1d81bd60592537b656396c Mon Sep 17 00:00:00 2001
From: Claude <claude@anthropic.local>
Date: Fri, 24 Apr 2026 00:54:29 +0000
Subject: [PATCH 2/2] #841: Fix NPE in DefectMissing for range unlint of absent
 lint

When a range-form '+unlint name:line-line' expression references a lint
name that is absent from the defects map, this.defects.get(name) returns
null and calling null.stream() throws NullPointerException.

Treat a null lines list the same way the non-range branch does: the
defect is missing unless the name is in the excluded list.
---
 src/main/java/org/eolang/lints/DefectMissing.java | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/main/java/org/eolang/lints/DefectMissing.java b/src/main/java/org/eolang/lints/DefectMissing.java
index c6c2ed17a..f292267d2 100644
--- a/src/main/java/org/eolang/lints/DefectMissing.java
+++ b/src/main/java/org/eolang/lints/DefectMissing.java
@@ -44,7 +44,11 @@ public Boolean apply(final String unlint) {
         final String name = split[0];
         final List<Integer> lines = this.defects.get(name);
         if (unlint.matches(String.format("%s:\\d+-\\d+", name))) {
-            missing = !lines.stream().allMatch(new UnlintInRange(unlint));
+            if (lines == null) {
+                missing = !this.excluded.contains(name);
+            } else {
+                missing = !lines.stream().allMatch(new UnlintInRange(unlint));
+            }
         } else {
             final Set<String> names;
             if (this.defects != null) {