Fix properties parsing for comment chars

Update `OriginTrackedPropertiesLoader` to correctly deal with property
values that happen to contain comment characters.

Prior this this commit, values of the following form would not be
parsed correctly:

	foo=bar!
	bar=spam

Closes gh-8647

spring-boot/src/main/java/org/springframework/boot/env/OriginTrackedPropertiesLoader.java

@@ -71,6 +71,7 @@ class OriginTrackedPropertiesLoader {
 			StringBuilder buffer = new StringBuilder();
 			while (reader.read()) {
 				String key = loadKey(buffer, reader).trim();
+				System.out.println(key);
 				if (expandLists && key.endsWith("[]")) {
 					key = key.substring(0, key.length() - 2);
 					int index = 0;
@@ -160,11 +161,19 @@ class OriginTrackedPropertiesLoader {
 		}
 
 		public boolean read() throws IOException {
+			return read(false);
+		}
+
+		public boolean read(boolean wrappedLine) throws IOException {
 			this.escaped = false;
 			this.character = this.reader.read();
 			this.columnNumber++;
-			skipLeadingWhitespace();
-			skipComment();
+			if (this.columnNumber == 0) {
+				skipLeadingWhitespace();
+				if (!wrappedLine) {
+					skipComment();
+				}
+			}
 			if (this.character == '\\') {
 				this.escaped = true;
 				readEscaped();
@@ -176,11 +185,9 @@ class OriginTrackedPropertiesLoader {
 		}
 
 		private void skipLeadingWhitespace() throws IOException {
-			if (this.columnNumber == 0) {
-				while (isWhiteSpace()) {
-					this.character = this.reader.read();
-					this.columnNumber++;
-				}
+			while (isWhiteSpace()) {
+				this.character = this.reader.read();
+				this.columnNumber++;
 			}
 		}
 
@@ -202,7 +209,7 @@ class OriginTrackedPropertiesLoader {
 			}
 			else if (this.character == '\n') {
 				this.columnNumber = -1;
-				read();
+				read(true);
 			}
 			else if (this.character == 'u') {
 				readUnicode();

spring-boot/src/test/java/org/springframework/boot/env/OriginTrackedPropertiesLoaderTests.java

@@ -52,7 +52,7 @@ public class OriginTrackedPropertiesLoaderTests {
 		Properties ours = new Properties();
 		new OriginTrackedPropertiesLoader(this.resource).load(false)
 				.forEach((k, v) -> ours.put(k, v.getValue()));
-		assertThat(java).isEqualTo(ours);
+		assertThat(ours).isEqualTo(java);
 	}
 
 	@Test
@@ -97,6 +97,20 @@ public class OriginTrackedPropertiesLoaderTests {
 		assertThat(getLocation(value)).isEqualTo("16:19");
 	}
 
+	@Test
+	public void getPropertyWithBang() throws Exception {
+		OriginTrackedValue value = this.properties.get("test-bang-property");
+		assertThat(getValue(value)).isEqualTo("foo!");
+		assertThat(getLocation(value)).isEqualTo("34:20");
+	}
+
+	@Test
+	public void getPropertyWithValueComment() throws Exception {
+		OriginTrackedValue value = this.properties.get("test-property-value-comment");
+		assertThat(getValue(value)).isEqualTo("foo !bar #foo");
+		assertThat(getLocation(value)).isEqualTo("36:29");
+	}
+
 	@Test
 	public void getPropertyWithCarriageReturn() throws Exception {
 		OriginTrackedValue value = this.properties.get("test-return-property");

spring-boot/src/test/resources/org/springframework/boot/env/test-properties.properties

@@ -31,3 +31,9 @@ language[pascal]=Lame
 test-multiline-immediate=\
 foo
 !commented-two=bang\
+test-bang-property=foo!
+another=bar
+test-property-value-comment=foo \
+!bar #foo
+test-multiline-immediate-bang=\
+!foo