Resolve "frontend float quantities validation"

Changelog: Fixed

gui/src/components/editQuantity/NumberEditQuantity.spec.js

@@ -45,11 +45,13 @@ describe('Test numberEditQuantity', () => {
     await waitFor(() => expect(numberFieldValueInput.value).toEqual('10'))
 
     await changeValue(numberFieldValueInput, '5')
+    await changeValue(numberFieldValueInput, '0')
     await changeValue(numberFieldValueInput, '')
 
-    await waitFor(() => expect(handleChange.mock.calls).toHaveLength(2))
+    await waitFor(() => expect(handleChange.mock.calls).toHaveLength(3))
     await waitFor(() => expect(handleChange.mock.calls[0][0]).toBe(5))
-    await waitFor(() => expect(handleChange.mock.calls[1][0]).toBe(undefined))
+    await waitFor(() => expect(handleChange.mock.calls[1][0]).toBe(0))
+    await waitFor(() => expect(handleChange.mock.calls[2][0]).toBe(undefined))
   })
 
   test.each([

gui/src/components/units/common.js

@@ -16,7 +16,7 @@
  * limitations under the License.
  */
 
-import {memoize, has} from 'lodash'
+import {memoize, has, isNil} from 'lodash'
 import {Unit} from './Unit'
 import { Unit as UnitMathJS } from 'mathjs'
 
@@ -53,7 +53,7 @@ export function parse(input, options) {
 
   try {
     const parseResults = parseInternal(input, options)
-    result.value = parseResults.value || undefined
+    result.value = isNil(parseResults.value) ? undefined : parseResults.value
     result.valueString = parseResults.valueString || undefined
     if (parseResults.unit?.units?.length) {
       result.unit = new Unit(parseResults.unit)