chore: Adds test coverage and fixes for negative value formatters (#1…

…22272)

* Adds tests for negative value formatters

* Adds tests for negative duration formatters

x-pack/plugins/observability/common/utils/formatters/duration.test.ts

@@ -71,7 +71,7 @@ describe('duration formatters', () => {
       [1000, '1,000.0 tpm'],
       [1000000, '1,000,000.0 tpm'],
     ])(
-      'displays the correct label when the number is integer and has zero decimals',
+      'displays the correct label when the number is a positive integer and has zero decimals',
       (value, formattedValue) => {
         expect(asTransactionRate(value)).toBe(formattedValue);
       }
@@ -89,12 +89,39 @@ describe('duration formatters', () => {
         expect(asTransactionRate(value)).toBe(formattedValue);
       }
     );
+
+    it.each([
+      [-1, '< 0.1 tpm'],
+      [-10, '< 0.1 tpm'],
+      [-100, '< 0.1 tpm'],
+      [-1000, '< 0.1 tpm'],
+      [-1000000, '< 0.1 tpm'],
+    ])(
+      'displays the correct label when the number is a negative integer and has zero decimals',
+      (value, formattedValue) => {
+        expect(asTransactionRate(value)).toBe(formattedValue);
+      }
+    );
+
+    it.each([
+      [-1.23, '< 0.1 tpm'],
+      [-12.34, '< 0.1 tpm'],
+      [-123.45, '< 0.1 tpm'],
+      [-1234.56, '< 0.1 tpm'],
+      [-1234567.89, '< 0.1 tpm'],
+    ])(
+      'displays the correct label when the number is negative and has decimal part',
+      (value, formattedValue) => {
+        expect(asTransactionRate(value)).toBe(formattedValue);
+      }
+    );
   });
 
   describe('asMilliseconds', () => {
     it('converts to formatted decimal milliseconds', () => {
       expect(asMillisecondDuration(0)).toEqual('0 ms');
     });
+
     it('formats correctly with undefined values', () => {
       expect(asMillisecondDuration(undefined)).toEqual('N/A');
     });

x-pack/plugins/observability/common/utils/formatters/formatters.test.ts

@@ -108,5 +108,29 @@ describe('formatters', () => {
     ])('formats as decimal when number is below 10 ', (value, formattedValue) => {
       expect(asDecimalOrInteger(value)).toBe(formattedValue);
     });
+
+    it.each([
+      [-0.123, '-0.1'],
+      [-1.234, '-1.2'],
+      [-9.876, '-9.9'],
+    ])(
+      'formats as decimal when number is negative and below 10 in absolute value',
+      (value, formattedValue) => {
+        expect(asDecimalOrInteger(value)).toEqual(formattedValue);
+      }
+    );
+
+    it.each([
+      [-12.34, '-12'],
+      [-123.45, '-123'],
+      [-1234.56, '-1,235'],
+      [-12345.67, '-12,346'],
+      [-12345678.9, '-12,345,679'],
+    ])(
+      'formats as integer when number is negative and above or equals 10 in absolute value',
+      (value, formattedValue) => {
+        expect(asDecimalOrInteger(value)).toEqual(formattedValue);
+      }
+    );
   });
 });

x-pack/plugins/observability/common/utils/formatters/formatters.ts

@@ -51,7 +51,7 @@ export type AsPercent = typeof asPercent;
 
 export function asDecimalOrInteger(value: number) {
   // exact 0 or above 10 should not have decimal
-  if (value === 0 || value >= 10) {
+  if (value === 0 || Math.abs(value) >= 10) {
     return asInteger(value);
   }
   return asDecimal(value);