Previously when rendering flattened source-maps, it was assumed that no
mapping would come from a line that is outside the lines of the actual
source content. It turns out this is not a valid assumption.
Now the code that renders flattened source-maps will handle such
mappings, with the additional benefit that the rendered source-map
will only contain mapping lines up to the last mapping, rather than a
mapping line for every content line.
Fixes#35709
PR Close#35718
If a package has a source-map but it does not provide
the actual content of the sources, then the source-map
flattening was crashing.
Now we ignore such mappings that have no source
since we are not able to compute the merged
mapping if there is no source file.
Fixes#35709
PR Close#35718
The library used by ngcc to update the source files (MagicString) is able
to generate a source-map but it is not able to account for any previous
source-map that the input text is already associated with.
There have been various attempts to fix this but none have been very
successful, since it is not a trivial problem to solve.
This commit contains a novel approach that is able to load up a tree of
source-files connected by source-maps and flatten them down into a single
source-map that maps directly from the final generated file to the original
sources referenced by the intermediate source-maps.
PR Close#35132
Pete Bacon Darwin