M6: calculation checks: a formula that reads a field the form doesn't have, and a script that builds the names it reads

calculation_order flags MissingField (a field deleted from under a sum, a
typo in notation, a script's getField; a group's name and a widget's
number count as there) and BuiltNames (a getField or AFSimple_Calculate
list built at run time, found as af::Site::Built in the same pass as the
literal names). form_calculation_order gives each field's formula and the
two new issues; form_fields shows a custom Calculate script; the
Calculation order page explains both in its row tooltips.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BfMGHQNgdq5yf5tKZHGR3z

parity/acrobat-features.toml

@@ -4679,8 +4679,8 @@ milestone = "M6"
 status = "shipped"
 commands = ["form.field.properties", "form.calculation_order"]
 tools = ["form_set_props", "form_fill", "form_calculation_order"]
-evidence = ["crates/forms/src/tests.rs::formats_validation_and_calculations_run_like_acrobat", "crates/forms/src/tests.rs::the_calculation_order_is_checked_fixed_and_kept", "crates/forms/src/tests.rs::a_calculation_order_with_gaps_and_extra_entries", "crates/forms/src/tests.rs::two_fields_with_one_name_keep_their_places_in_the_order", "crates/engine/src/tests.rs::setting_the_calculation_order_recalculates_and_undoes", "crates/automation/tests/it/automation.rs::the_calculation_order_is_read_fixed_and_set", "crates/ui-egui/tests/it/prepare.rs::the_calculation_order_is_moved_dragged_and_fixed", "crates/engine/src/tests.rs::checkbox_and_rank_changes_recalculate_ordered_dependents", "crates/engine/src/tests.rs::dynamic_calculation_reads_and_side_effects_reach_later_fields"]
-notes = "/CO order, then other calculated fields; recalculated after every fill and Clear form. Order editing: Prepare a form ▸ Calculation order lists the calculated fields in order with their formulas and values, Up/Down arrows (as Acrobat's Set Field Calculation Order dialog), Alt+Up/Down and drag, says which fields read a field calculated later, which read each other in a loop and which /CO leaves out, and Fix order moves only what must move; on the page it numbers each calculated field's step and draws arrows from the fields the focused field reads and to the fields that read it; form_calculation_order reads, sets, moves and fixes it. A new calculation joins the end of /CO and an edited one keeps its place. Acrobat's dialog is known from Adobe's help summary only, not yet observed."
+evidence = ["crates/forms/src/tests.rs::formats_validation_and_calculations_run_like_acrobat", "crates/forms/src/tests.rs::the_calculation_order_is_checked_fixed_and_kept", "crates/forms/src/tests.rs::a_calculation_order_with_gaps_and_extra_entries", "crates/forms/src/tests.rs::two_fields_with_one_name_keep_their_places_in_the_order", "crates/engine/src/tests.rs::setting_the_calculation_order_recalculates_and_undoes", "crates/automation/tests/it/automation.rs::the_calculation_order_is_read_fixed_and_set", "crates/ui-egui/tests/it/prepare.rs::the_calculation_order_is_moved_dragged_and_fixed", "crates/engine/src/tests.rs::checkbox_and_rank_changes_recalculate_ordered_dependents", "crates/engine/src/tests.rs::dynamic_calculation_reads_and_side_effects_reach_later_fields", "crates/forms/src/tests.rs::missing_fields_and_built_names_are_flagged", "crates/forms/src/calc_order.rs::a_read_name_finds_a_field_a_group_or_a_widget", "crates/forms/src/af/tests.rs::names_built_at_run_time_are_noticed", "crates/automation/tests/it/automation.rs::the_calculation_order_shows_formulas_and_what_they_cannot_read"]
+notes = "/CO order, then other calculated fields; recalculated after every fill and Clear form. Order editing: Prepare a form ▸ Calculation order lists the calculated fields in order with their formulas and values, Up/Down arrows (as Acrobat's Set Field Calculation Order dialog), Alt+Up/Down and drag, says which fields read a field calculated later, which read each other in a loop and which /CO leaves out, and Fix order moves only what must move; on the page it numbers each calculated field's step and draws arrows from the fields the focused field reads and to the fields that read it; form_calculation_order reads, sets, moves and fixes it. Each formula is also checked against the form: a read of a field the form doesn't have (a field deleted from under a sum, a typo in notation, a script's getField) and a script that builds the names it reads at run time are flagged, in form_calculation_order (which also gives each formula) and in the page's row tooltips. A new calculation joins the end of /CO and an edited one keeps its place. Acrobat's dialog is known from Adobe's help summary only, not yet observed."
 
 [[feature]]
 id = "form.event-order"
@@ -5051,8 +5051,8 @@ milestone = "M6"
 status = "shipped"
 commands = ["form.field.properties"]
 tools = ["form_set_props", "form_fill"]
-evidence = ["crates/ui-egui/tests/it/prepare.rs::format_validate_and_calculate_tabs", "crates/automation/tests/it/automation.rs::form_formats_and_calculations_through_tools", "crates/forms/src/tests.rs::renaming_a_field_renames_it_in_the_calculations_that_read_it", "crates/forms/src/tests.rs::a_rename_reaches_every_stored_form_of_a_calculation", "crates/automation/tests/it/automation.rs::renaming_a_field_keeps_the_formulas_that_read_it", "crates/ui-egui/tests/it/prepare.rs::renaming_a_field_says_how_many_calculations_now_use_the_new_name", "crates/forms/src/af/tests.rs::a_regex_after_a_condition_is_not_read_as_code", "crates/forms/src/af/tests.rs::a_line_comment_ends_at_any_line_terminator", "crates/forms/src/af/tests.rs::a_token_ends_at_a_line_separator"]
-notes = "sum/product/average/min/max of picked fields, simplified field notation; custom script pending. Renaming a field renames it in the calculations that read it (field lists, notation, and getField calls naming it in a string literal), in the rename's undo step; Field Properties says how many changed and form_set_props lists them. Not rewritten: names built at run time, other events' scripts, document-level scripts. A regular expression that starts a statement right after a `}` is still read as code, so a quote inside one can hide the getField calls after it from a rename and from the calculation order. Whether Acrobat does this is not observed."
+evidence = ["crates/ui-egui/tests/it/prepare.rs::format_validate_and_calculate_tabs", "crates/automation/tests/it/automation.rs::form_formats_and_calculations_through_tools", "crates/forms/src/tests.rs::renaming_a_field_renames_it_in_the_calculations_that_read_it", "crates/forms/src/tests.rs::a_rename_reaches_every_stored_form_of_a_calculation", "crates/automation/tests/it/automation.rs::renaming_a_field_keeps_the_formulas_that_read_it", "crates/ui-egui/tests/it/prepare.rs::renaming_a_field_says_how_many_calculations_now_use_the_new_name", "crates/forms/src/af/tests.rs::a_regex_after_a_condition_is_not_read_as_code", "crates/forms/src/af/tests.rs::a_line_comment_ends_at_any_line_terminator", "crates/forms/src/af/tests.rs::a_token_ends_at_a_line_separator", "crates/automation/tests/it/automation.rs::the_calculation_order_shows_formulas_and_what_they_cannot_read"]
+notes = "sum/product/average/min/max of picked fields, simplified field notation; custom script pending. form_fields shows a custom Calculate script as {script}. Renaming a field renames it in the calculations that read it (field lists, notation, and getField calls naming it in a string literal), in the rename's undo step; Field Properties says how many changed and form_set_props lists them. Not rewritten: names built at run time, other events' scripts, document-level scripts. A regular expression that starts a statement right after a `}` is still read as code, so a quote inside one can hide the getField calls after it from a rename and from the calculation order. Whether Acrobat does this is not observed."
 
 [[feature]]
 id = "form.props-selection-change"