command/format: Don't panic when item removed from list of objects

Due to these tests happening in the wrong order, removing an object from
the end of a sequence of objects would previously cause a bounds-check
panic.

Rather than a more severe rework of the logic here, for now we'll just
introduce an extra precondition to prevent the panic. The code that
follows already handles the case where there _is_ no new object (i.e. the
"old" object is being deleted) as long as we're able to pass through this
type-checking logic.

The new "JSON list of objects - removing item" test covers this problem
by rendering a diff for an object being removed from the end of a list
of objects within a JSON value.
This commit is contained in:
Martin Atkins 2019-03-19 15:21:32 -07:00
parent 35df450dc0
commit e918fa83ec
2 changed files with 37 additions and 2 deletions

View File

@ -1067,7 +1067,7 @@ func ctySequenceDiff(old, new []cty.Value) []*plans.Change {
var oldI, newI, lcsI int
for oldI < len(old) || newI < len(new) || lcsI < len(lcs) {
for oldI < len(old) && (lcsI >= len(lcs) || !old[oldI].RawEquals(lcs[lcsI])) {
isObjectDiff := old[oldI].Type().IsObjectType() && new[newI].Type().IsObjectType()
isObjectDiff := old[oldI].Type().IsObjectType() && (newI >= len(new) || new[newI].Type().IsObjectType())
if isObjectDiff && newI < len(new) {
ret = append(ret, &plans.Change{
Action: plans.Update,

View File

@ -761,7 +761,7 @@ func TestResourceChange_JSON(t *testing.T) {
}
`,
},
"JSON list of objects": {
"JSON list of objects - adding item": {
Action: plans.Update,
Mode: addrs.ManagedResourceMode,
Before: cty.ObjectVal(map[string]cty.Value{
@ -794,6 +794,41 @@ func TestResourceChange_JSON(t *testing.T) {
]
)
}
`,
},
"JSON list of objects - removing item": {
Action: plans.Update,
Mode: addrs.ManagedResourceMode,
Before: cty.ObjectVal(map[string]cty.Value{
"id": cty.StringVal("i-02ae66f368e8518a9"),
"json_field": cty.StringVal(`[{"one": "111"}, {"two": "222"}]`),
}),
After: cty.ObjectVal(map[string]cty.Value{
"id": cty.UnknownVal(cty.String),
"json_field": cty.StringVal(`[{"one": "111"}]`),
}),
Schema: &configschema.Block{
Attributes: map[string]*configschema.Attribute{
"id": {Type: cty.String, Optional: true, Computed: true},
"json_field": {Type: cty.String, Optional: true},
},
},
RequiredReplace: cty.NewPathSet(),
Tainted: false,
ExpectedOutput: ` # test_instance.example will be updated in-place
~ resource "test_instance" "example" {
~ id = "i-02ae66f368e8518a9" -> (known after apply)
~ json_field = jsonencode(
~ [
{
one = "111"
},
- {
- two = "222"
},
]
)
}
`,
},
"JSON object with list of objects": {