Robust test assertions

Use precise, informative assertions in tests to provide clear feedback when tests fail and verify the correct behavior rather than implementation details.

Key practices:

1. Use assertion methods with descriptive messages: Replace plain assert statements with proper test framework assertions that provide clear error messages.

   // Instead of this:
   assert valueCount == 1;
      
   // Do this:
   assertEquals(1, valueCount, "Multi-values make chunking more complex, and it's not a real case yet");
   

2. Use expectThrows for exception testing: Replace try-catch blocks with more readable and concise expectThrows pattern.

   // Instead of this:
   try {
       createComponents("my_analyzer", analyzerSettings, testAnalysis.tokenizer, testAnalysis.charFilter, testAnalysis.tokenFilter);
       fail("expected failure");
   } catch (IllegalArgumentException e) {
       // assertions
   }
      
   // Do this:
   IllegalArgumentException e = expectThrows(
       IllegalArgumentException.class,
       () -> createComponents("my_analyzer", analyzerSettings, testAnalysis.tokenizer, testAnalysis.charFilter, testAnalysis.tokenFilter)
   );
   // assertions on exception
   

3. Focus assertions on behavior, not implementation details: Verify that the code does the right thing, not how it does it.

   // Instead of verifying exact implementation details:
   verify(coordinatingIndexingPressure).increment(1, bytesUsed(doc0Source));
   verify(coordinatingIndexingPressure).increment(1, bytesUsed(doc1Source));
      
   // Verify the essential behavior:
   verify(coordinatingIndexingPressure, times(6)).increment(eq(1), longThat(l -> l > 0));
   

4. Verify all relevant fields: Assert on all important aspects of the test output, not just a subset.

5. Randomize test values: Use randomized values instead of hardcoded constants to ensure tests catch edge cases.

   // Instead of hardcoded values:
   String apiKeyId = "test-id";
      
   // Use randomization:
   String apiKeyId = randomAlphaOfLength(20);
   

6. Use appropriate matchers: For values that may vary, use flexible assertions like greaterThanOrEqualTo() instead of strict equality.