633 - fix backslack comma behaviour

spec/src/main/asciidoc/configexamples.asciidoc

@@ -324,7 +324,7 @@ The table below defines the conversion rules, including some special edge case s
 | "\,"
 | String[]
 | getValue
-| throws `NoSuchElementException`
+| {","}
 
 
 | "\,"
@@ -335,12 +335,12 @@ The table below defines the conversion rules, including some special edge case s
 | "\,"
 | String[]
 | getOptionalValue
-| Optional.empty()
+| Optional.of({","})
 
 | "\,"
 | String
 | getOptionalValues
-| Optional.empty()
+| Optional.of(List.of(","))
 
 | ",,"
 | String

spec/src/main/asciidoc/release_notes.asciidoc

@@ -34,7 +34,7 @@ previous behaviour.
 - Empty value or other special characters are no longer a valid config value for a particular return type. Refer to the earlier section of this spec for more details.
 In the previous release, the empty value was returned as an empty value. From now on, the empty value will cause `NoSuchElementException` to be thrown.
 (link:https://github.com/eclipse/microprofile-config/issues/446[446]) (link:https://github.com/eclipse/microprofile-config/issues/531[531])
-(link:https://github.com/eclipse/microprofile-config/issues/532[532]) (link:https://github.com/eclipse/microprofile-config/issues/397[397])
+(link:https://github.com/eclipse/microprofile-config/issues/532[532]) (link:https://github.com/eclipse/microprofile-config/issues/397[397]) (link:https://github.com/eclipse/microprofile-config/issues/633[633])
 
 === API/SPI Changes
 - Convenience methods have been added to Config allowing for the retrieval of multi-valued properties as lists instead of arrays (link:https://github.com/eclipse/microprofile-config/issues/496[#496])

tck/src/main/java/org/eclipse/microprofile/config/tck/emptyvalue/EmptyValuesTestProgrammaticLookup.java

@@ -109,9 +109,11 @@ public void testCommaStringGetOptionalValue() {
  assertConfigurationNotPresentForOptionalMultiple("comma.string");
  }
 
- @Test(expectedExceptions = NoSuchElementException.class)
+ @Test
  public void testBackslashCommaStringGetValueArray() {
  String[] values = config.getValue("backslash.comma.string", String[].class);
+ Assert.assertEquals(values, new String[]{","});
+
  }
 
  @Test
@@ -120,6 +122,12 @@ public void testBackslashCommaStringGetValue() {
  Assert.assertEquals(value, "\\,");
  }
 
+ @Test
+ public void testBackslashCommaStringGetOptionalValueAsArrayorList() {
+ Assert.assertEquals(config.getOptionalValue("backslash.comma.string", String[].class).get(), new String[]{","});
+ Assert.assertEquals(config.getOptionalValues("backslash.comma.string", String.class).get(), Arrays.asList(","));
+ }
+
  @Test
  public void testBackslashCommaStringGetOptionalValue() {
  Assert.assertEquals(config.getOptionalValue("backslash.comma.string", String.class).get(), "\\,");