mdiff: convert a few block definitions from lists to tuples
These were flagged by adding type hints. Some places were using a tuple of 4
ints to define a block, and others were using a list of 4. A tuple is better
for typing, because we can define the length and the type of each entry. One of
the places had to redefine the tuple, since writing to a tuple at an index isn't
supported.
This change spills out into the tests, and archeology says it was added to the
repo in this state. There was no reason given for the divergence, and I suspect
it wasn't intentional.
It looks like `splitblock()` is completely unused in the codebase.
#ifndef HG_BDIFF_H
#define HG_BDIFF_H
#include "compat.h"
struct bdiff_line {
int hash, n, e;
ssize_t len;
const char *l;
};
struct bdiff_hunk;
struct bdiff_hunk {
int a1, a2, b1, b2;
struct bdiff_hunk *next;
};
int bdiff_splitlines(const char *a, ssize_t len, struct bdiff_line **lr);
int bdiff_diff(struct bdiff_line *a, int an, struct bdiff_line *b, int bn,
struct bdiff_hunk *base);
void bdiff_freehunks(struct bdiff_hunk *l);
#endif