fix: handle ~= and != version operators in Python dependency name parsing

getDependencyName() only recognized >, <, and = as version operator
characters, causing ~ from ~= (compatibility) and ! from != (exclusion)
to be included in the package name (e.g. "urllib3~", "click!").

Replaced the three-index approach with a loop that recognizes all PEP 508
version operator characters (>, <, =, ~, !).

Fixes TC-4041

Assisted-by: Claude Code

Author: a-oren

src/main/java/io/github/guacsec/trustifyda/utils/PythonControllerBase.java

@@ -388,31 +388,24 @@ public static String getDependencyName(String dep) {
         requirement = requirement.substring(0, extrasStart) + requirement.substring(extrasEnd + 1);
       }
     }
-    int rightTriangleBracket = requirement.indexOf(">");
-    int leftTriangleBracket = requirement.indexOf("<");
-    int equalsSign = requirement.indexOf("=");
-    int minimumIndex = getFirstSign(rightTriangleBracket, leftTriangleBracket, equalsSign);
+    // Find the first PEP 508 version operator character (~=, !=, ==, >=, <=, >, <, ===)
+    int firstOperatorChar = -1;
+    for (int i = 0; i < requirement.length(); i++) {
+      char c = requirement.charAt(i);
+      if (c == '>' || c == '<' || c == '=' || c == '~' || c == '!') {
+        firstOperatorChar = i;
+        break;
+      }
+    }
     String depName;
-    if (rightTriangleBracket == -1 && leftTriangleBracket == -1 && equalsSign == -1) {
+    if (firstOperatorChar == -1) {
       depName = requirement;
     } else {
-      depName = requirement.substring(0, minimumIndex);
+      depName = requirement.substring(0, firstOperatorChar);
     }
     return depName.trim();
   }
 
-  private static int getFirstSign(
-      int rightTriangleBracket, int leftTriangleBracket, int equalsSign) {
-    rightTriangleBracket = rightTriangleBracket == -1 ? 999 : rightTriangleBracket;
-    leftTriangleBracket = leftTriangleBracket == -1 ? 999 : leftTriangleBracket;
-    equalsSign = equalsSign == -1 ? 999 : equalsSign;
-    return equalsSign < leftTriangleBracket && equalsSign < rightTriangleBracket
-        ? equalsSign
-        : (leftTriangleBracket < equalsSign && leftTriangleBracket < rightTriangleBracket
-            ? leftTriangleBracket
-            : rightTriangleBracket);
-  }
-
   static List<String> splitPipShowLines(String pipShowOutput) {
     return Arrays.stream(
             pipShowOutput.split(System.lineSeparator() + "---" + System.lineSeparator()))

src/test/java/io/github/guacsec/trustifyda/utils/PythonControllerRealEnvTest.java

@@ -301,6 +301,16 @@ void get_Dependency_Name_with_markers() {
         PythonControllerRealEnv.getDependencyName("certifi==2023.7.22 ; python_version >= \"3\""));
   }
 
+  /** Verifies getDependencyName handles compatibility (~=) and exclusion (!=) operators. */
+  @Test
+  void get_Dependency_Name_with_compatibility_and_exclusion_operators() {
+    assertEquals("urllib3", PythonControllerRealEnv.getDependencyName("urllib3~=1.26.0"));
+    assertEquals("click", PythonControllerRealEnv.getDependencyName("click!=7.1.1"));
+    assertEquals("certifi", PythonControllerRealEnv.getDependencyName("certifi>=2021.0.0"));
+    assertEquals("package", PythonControllerRealEnv.getDependencyName("package~=2.0"));
+    assertEquals("package", PythonControllerRealEnv.getDependencyName("package!=1.0.0"));
+  }
+
   /** Verifies getDependencyName strips PEP 508 extras from requirements. */
   @Test
   void get_Dependency_Name_with_extras() {
@@ -313,6 +323,17 @@ void get_Dependency_Name_with_extras() {
             "package[extra1]>=1.0 ; python_version >= \"3.8\""));
   }
 
+  /** Verifies getDependencyName handles extras combined with special version operators. */
+  @Test
+  void get_Dependency_Name_with_extras_and_special_operators() {
+    assertEquals(
+        "requests", PythonControllerRealEnv.getDependencyName("requests[security,socks]==2.25.1"));
+    assertEquals("httpx", PythonControllerRealEnv.getDependencyName("httpx [http2] >=0.23.0"));
+    assertEquals(
+        "package",
+        PythonControllerRealEnv.getDependencyName("package[extra]~=1.0 ; python_version >= \"3\""));
+  }
+
   @Test
   void automaticallyInstallPackageOnEnvironment() {
     assertFalse(pythonControllerRealEnv.automaticallyInstallPackageOnEnvironment());