unison/unison-src/transcripts/diff.md

.> builtins.mergeio

x = 23

.b1> add
.b1> alias.term x fslkdjflskdjflksjdf
.> fork b1 b2
.b2> alias.term x abc

fslkdjflskdjflksjdf = 663

.b0> add
.> merge b0 b1
.> diff.namespace b1 b2

Things we want to test:

• Diffing identical namespaces
• Adds, removes, updates (with and without metadata updates)
  • Adds with multiple names
  • Adds with multiple names and different metadata on each
• Moved and copied definitions
  • Moves that have more that 1 initial or final name
• ... terms and types
• New patches, modified patches, deleted patches, moved patches
• With and without propagated updates

fromJust = 1
b = 2
bdependent = b
c = 3
helloWorld = "Hello, world!"

type A a = A Nat
ability X a1 a2 where x : Nat

.ns1> add
.ns1> alias.term fromJust fromJust'
.ns1> alias.term helloWorld helloWorld2
.ns1> link b fromJust
.ns1> fork .ns1 .ns2
.ns1> cd .

Here's what we've done so far:

.> diff.namespace nothing ns1
.> diff.namespace ns1 ns2

fromJust = "asldkfjasldkfj"

.ns1b> add
.> merge ns1b ns1

fromJust = 99
b = "oog"
d = 4
e = 5
f = 6
unique type Y a b = Y a b

.ns2> update
.ns2> links fromJust
.> diff.namespace ns1 ns2
.> alias.term ns2.d ns2.d'
.> alias.type ns2.A ns2.A'
.> alias.type ns2.X ns2.X'
.> diff.namespace ns1 ns2
.> link ns1.c ns2.f
.> link ns2.c ns2.c
.> diff.namespace ns1 ns2
.> unlink ns2.b ns2.fromJust
.> diff.namespace ns1 ns2
.> alias.type ns1.X ns1.X2
.> alias.type ns2.A' ns2.A''
.> view.patch ns2.patch
.> fork ns2 ns3
.> alias.term ns2.fromJust' ns2.yoohoo
.> delete.term ns2.fromJust'
.> diff.namespace ns3 ns2

bdependent = "banana"

.ns3> update
.> diff.namespace ns2 ns3

Two different auto-propagated changes creating a name conflict

Currently, the auto-propagated name-conflicted definitions are not explicitly shown, only their also-conflicted dependency is shown.

a = 333
b = a + 1

.nsx> add
.> fork nsx nsy
.> fork nsx nsz

a = 444

.nsy> update

a = 555

.nsz> update
.> merge nsy nsw

.> merge nsz nsw

.> diff.namespace nsx nsw
.nsw> view a b

a = 777

.nsw> update
.nsw> view a b

Updates: -- 1 to 1

New name conflicts: -- updates where RHS has multiple hashes (excluding when RHS=LHS)

1. foo#jk19sm5bf8 : Nat - do we want to force a hashqualified? Arya thinks so ↓
2. ┌ foo#0ja1qfpej6 : Nat
3. └ foo#jk19sm5bf8 : Nat

Resolved name conflicts: -- updates where LHS had multiple hashes and RHS has one

4. ┌ bar#0ja1qfpej6 : Nat
5. └ bar#jk19sm5bf8 : Nat ↓
6. bar#jk19sm5bf8 : Nat

Display issues to fixup

• [d] Do we want to surface new edit conflicts in patches?
• [t] two different auto-propagated changes creating a name conflict should show up somewhere besides the auto-propagate count
• [t] Things look screwy when the type signature doesn't fit and has to get broken up into multiple lines. Maybe just disallow that?
• [d] Delete blank line in between copies / renames entries if all entries are 1 to 1 see todo in the code
• incorrectly calculated bracket alignment on hashqualified "Name changes" (delete.output.md)
• just handle deletion of isPropagated in propagate function, leave HandleInput alone (assuming this does the trick)
• might want unqualified names to be qualified sometimes:
• if a name is updated to a not-yet-named reference, it's shown as both an update and an add
• similarly, if a conflicted name is resolved by deleting the last name to a reference, I (arya) suspect it will show up as a Remove
• [d] Maybe group and/or add headings to the types, constructors, terms
• check whether creating a name conflict + adding metadata puts the update in both categories; if it does, then filter out metadataUpdates from the other categories
• add tagging of propagated updates to test propagated updates output
• missing old names in deletion ppe (delete.output.md) (superseded by #1143)
• delete.term has some bonkers output
• Make a decision about how we want to show constructors in the diff
• When you delete a name with metadata, it also shows up in updates section with the deleted metadata.
• An add with new metadata is getting characterized as an update
• can there be a metadata-only update where it's not a singleton old and new reference
• 12.patch patch needs a space
• This looks like garbage
• Extra 2 blank lines at the end of the add section
• Fix alignment issues with buildTable, convert to column3M (to be written)
• adding an alias is showing up as an Add and a Copy; should just show as Copy
• removing one of multiple aliases appears in removes + moves + copies section
• some overlapping cases between Moves and Copies^
• Maybe don't list the type signature twice for aliases?