change message styling rules

Message styling purposly doesn’t require a whitespace after a closing
tag to make something like ~un~believable work. However it also breaks
_Programmierer_innen_ and other example where the tag is repeated as a
non tag in the word.
Therefor we change the rules that if a closing tag is followed by a higher
order closing tag (a closing tag followed by an end block or white space)
we ignore the first closing tag. But only if we don’t read another tag open.
This commit is contained in:
Daniel Gultsch 2018-12-09 18:26:27 +01:00
parent 1a1bfb3246
commit 6a06bcfd58

View file

@ -35,102 +35,125 @@ import java.util.List;
public class ImStyleParser { public class ImStyleParser {
private final static List<Character> KEYWORDS = Arrays.asList('*', '_', '~', '`'); private final static List<Character> KEYWORDS = Arrays.asList('*', '_', '~', '`');
private final static List<Character> NO_SUB_PARSING_KEYWORDS = Arrays.asList('`'); private final static List<Character> NO_SUB_PARSING_KEYWORDS = Arrays.asList('`');
private final static List<Character> BLOCK_KEYWORDS = Arrays.asList('`'); private final static List<Character> BLOCK_KEYWORDS = Arrays.asList('`');
private final static boolean ALLOW_EMPTY = false; private final static boolean ALLOW_EMPTY = false;
private final static boolean PARSE_HIGHER_ORDER_END = true;
public static List<Style> parse(CharSequence text) { public static List<Style> parse(CharSequence text) {
return parse(text, 0, text.length() - 1); return parse(text, 0, text.length() - 1);
} }
public static List<Style> parse(CharSequence text, int start, int end) { public static List<Style> parse(CharSequence text, int start, int end) {
List<Style> styles = new ArrayList<>(); List<Style> styles = new ArrayList<>();
for (int i = start; i <= end; ++i) { for (int i = start; i <= end; ++i) {
char c = text.charAt(i); char c = text.charAt(i);
if (KEYWORDS.contains(c) && precededByWhiteSpace(text, i, start) && !followedByWhitespace(text, i, end)) { if (KEYWORDS.contains(c) && precededByWhiteSpace(text, i, start) && !followedByWhitespace(text, i, end)) {
if (BLOCK_KEYWORDS.contains(c) && isCharRepeatedTwoTimes(text, c, i + 1, end)) { if (BLOCK_KEYWORDS.contains(c) && isCharRepeatedTwoTimes(text, c, i + 1, end)) {
int to = seekEndBlock(text, c, i + 3, end); int to = seekEndBlock(text, c, i + 3, end);
if (to != -1 && (to != i + 5 || ALLOW_EMPTY)) { if (to != -1 && (to != i + 5 || ALLOW_EMPTY)) {
String keyword = String.valueOf(c) + String.valueOf(c) + String.valueOf(c); String keyword = String.valueOf(c) + String.valueOf(c) + String.valueOf(c);
styles.add(new Style(keyword, i, to)); styles.add(new Style(keyword, i, to));
i = to; i = to;
continue; continue;
} }
} }
int to = seekEnd(text, c, i + 1, end); int to = seekEnd(text, c, i + 1, end);
if (to != -1 && (to != i + 1 || ALLOW_EMPTY)) { if (to != -1 && (to != i + 1 || ALLOW_EMPTY)) {
styles.add(new Style(c, i, to)); styles.add(new Style(c, i, to));
if (!NO_SUB_PARSING_KEYWORDS.contains(c)) { if (!NO_SUB_PARSING_KEYWORDS.contains(c)) {
styles.addAll(parse(text, i + 1, to - 1)); styles.addAll(parse(text, i + 1, to - 1));
} }
i = to; i = to;
} }
} }
} }
return styles; return styles;
} }
private static boolean isCharRepeatedTwoTimes(CharSequence text, char c, int index, int end) { private static boolean isCharRepeatedTwoTimes(CharSequence text, char c, int index, int end) {
return index + 1 <= end && text.charAt(index) == c && text.charAt(index+1) == c; return index + 1 <= end && text.charAt(index) == c && text.charAt(index + 1) == c;
} }
private static boolean precededByWhiteSpace(CharSequence text, int index, int start) { private static boolean precededByWhiteSpace(CharSequence text, int index, int start) {
return index == start || Character.isWhitespace(text.charAt(index - 1)); return index == start || Character.isWhitespace(text.charAt(index - 1));
} }
private static boolean followedByWhitespace(CharSequence text, int index, int end) { private static boolean followedByWhitespace(CharSequence text, int index, int end) {
return index >= end || Character.isWhitespace(text.charAt(index + 1)); return index >= end || Character.isWhitespace(text.charAt(index + 1));
} }
private static int seekEnd(CharSequence text, char needle, int start, int end) { private static int seekEnd(CharSequence text, char needle, int start, int end) {
for (int i = start; i <= end; ++i) { for (int i = start; i <= end; ++i) {
char c = text.charAt(i); char c = text.charAt(i);
if (c == needle && !Character.isWhitespace(text.charAt(i - 1))) { if (c == needle && !Character.isWhitespace(text.charAt(i - 1))) {
return i; if (!PARSE_HIGHER_ORDER_END || followedByWhitespace(text, i, end)) {
} else if (c == '\n') { return i;
return -1; } else {
} int higherOrder = seekHigherOrderEndWithoutNewBeginning(text, needle, i + 1, end);
} if (higherOrder != -1) {
return -1; return higherOrder;
} }
return i;
}
} else if (c == '\n') {
return -1;
}
}
return -1;
}
private static int seekEndBlock(CharSequence text, char needle, int start, int end) { private static int seekHigherOrderEndWithoutNewBeginning(CharSequence text, char needle, int start, int end) {
for (int i = start; i <= end; ++i) { for (int i = start; i <= end; ++i) {
char c = text.charAt(i); char c = text.charAt(i);
if (c == needle && isCharRepeatedTwoTimes(text, needle, i + 1, end)) { if (c == needle && precededByWhiteSpace(text, i, start) && !followedByWhitespace(text, i, end)) {
return i + 2; return -1; // new beginning
} } else if (c == needle && !Character.isWhitespace(text.charAt(i - 1)) && followedByWhitespace(text, i, end)) {
} return i;
return -1; } else if (c == '\n') {
} return -1;
}
}
return -1;
}
public static class Style { private static int seekEndBlock(CharSequence text, char needle, int start, int end) {
for (int i = start; i <= end; ++i) {
char c = text.charAt(i);
if (c == needle && isCharRepeatedTwoTimes(text, needle, i + 1, end)) {
return i + 2;
}
}
return -1;
}
private final String keyword; public static class Style {
private final int start;
private final int end;
public Style(char character, int start, int end) { private final String keyword;
this(String.valueOf(character), start, end); private final int start;
} private final int end;
public Style(String keyword, int start, int end) { public Style(char character, int start, int end) {
this.keyword = keyword; this(String.valueOf(character), start, end);
this.start = start; }
this.end = end;
}
public String getKeyword() { public Style(String keyword, int start, int end) {
return keyword; this.keyword = keyword;
} this.start = start;
this.end = end;
}
public int getStart() { public String getKeyword() {
return start; return keyword;
} }
public int getEnd() { public int getStart() {
return end; return start;
} }
}
public int getEnd() {
return end;
}
}
} }