Method diffTrees

src/main/java/club/qqtim/diff/DiffUtil.java:48–76

(Map<String, String> treeFrom, Map<String, String> treeTo)

    }

    public static String diffTrees(Map<String, String> treeFrom, Map<String, String> treeTo) {
        StringBuilder output = new StringBuilder();
        final Map<String, List<String>> pathObjectIds = compareTrees(treeFrom, treeTo);
        pathObjectIds.forEach((path, objectIds) -> {
            final String from = objectIds.get(0);
            final String to = objectIds.get(1);
            if (!Objects.equals(from, to)) {
                if (from == null) {
                    output.append(String.format("\ncreated file: %s\n", path));
                    final List<LineObject> lineObjects = convertObjectContentToLines(to);
                    lineObjects.forEach(lineObject -> lineObject.setAction(ConstantVal.PLUS));
                    final String diffResult = lineObjects.stream().map(LineObject::toString).collect(Collectors.joining(System.lineSeparator()));
                    output.append(diffResult);
                } else if (to == null) {
                    output.append(String.format("\ndeleted file: %s\n", path));
                    final List<LineObject> lineObjects = convertObjectContentToLines(from);
                    lineObjects.forEach(lineObject -> lineObject.setAction(ConstantVal.MINUS));
                    final String diffResult = lineObjects.stream().map(LineObject::toString).collect(Collectors.joining(System.lineSeparator()));
                    output.append(diffResult);
                } else {
                    output.append(String.format("\nchange file: %s\n", path));
                    final List<LineObject> lineObjects = diffBlobs(from, to);
                    final String diffResult = lineObjects.stream().map(LineObject::toString).collect(Collectors.joining(System.lineSeparator()));
                    output.append(diffResult);
                }
            }
        });
        return output.toString();
    }

    /**
     * https://qqtim.club/2020/06/14/git-myers-diff/