Fix optional arguments in scalar computed column functions (#2229)

.changeset/curly-tigers-glow.md

@@ -0,0 +1,6 @@
+---
+"graphile-build-pg": patch
+"postgraphile": patch
+---
+
+Fixes bug handling optional arguments to computed column functions.

graphile-build/graphile-build-pg/src/plugins/PgCustomTypeFieldPlugin.ts

@@ -12,6 +12,7 @@ import type {
   PgInsertSingleStep,
   PgResource,
   PgResourceParameter,
+  PgSelectArgumentDigest,
   PgSelectArgumentSpec,
   PgSelectStep,
   PgTypedExecutableStep,
@@ -1100,25 +1101,42 @@ function modFields(
                     typeof resource.from === "function"
                   ) {
                     // This is a scalar computed attribute, let's inline the expression
-                    const placeholders = selectArgs.map((arg, i) => {
-                      if (i === 0) {
-                        return $row.getClassStep().alias;
-                      } else if ("pgCodec" in arg && arg.pgCodec) {
-                        return $row.placeholder(arg.step, arg.pgCodec);
-                      } else {
-                        return $row.placeholder(
-                          arg.step as PgTypedExecutableStep<any>,
-                        );
-                      }
-                    });
+                    const newSelectArgs = selectArgs.map(
+                      (
+                        arg,
+                        i,
+                      ): PgSelectArgumentDigest & {
+                        // We _MUST_ set `name` if we're told one
+                        name: string | undefined;
+                      } => {
+                        const { name } = arg;
+                        if (i === 0) {
+                          return {
+                            name,
+                            placeholder: $row.getClassStep().alias,
+                          };
+                        } else if ("pgCodec" in arg && arg.pgCodec) {
+                          return {
+                            name,
+                            placeholder: $row.placeholder(
+                              arg.step,
+                              arg.pgCodec,
+                            ),
+                          };
+                        } else {
+                          return {
+                            name,
+                            placeholder: $row.placeholder(
+                              arg.step as PgTypedExecutableStep<any>,
+                            ),
+                          };
+                        }
+                      },
+                    );
                     return pgClassExpression(
                       $row,
                       resource.codec,
-                    )`${resource.from(
-                      ...placeholders.map((placeholder) => ({
-                        placeholder,
-                      })),
-                    )}`;
+                    )`${resource.from(...newSelectArgs)}`;
                   }
                   // PERF: or here, if scalar add select to `$row`?
                   return resource.execute(selectArgs);

postgraphile/postgraphile/__tests__/kitchen-sink-schema.sql

@@ -402,6 +402,14 @@ create function c.person_friends(person c.person) returns setof c.person as $$ s
 comment on function c.person_friends(c.person) is E'@sortable';
 create function c.person_first_post(person c.person) returns a.post as $$ select * from a.post where a.post.author_id = person.id order by id asc limit 1 $$ language sql stable;
 comment on function c.person_first_post(c.person) is 'The first post by the person.';
+
+-- Same as optional_missing_middle_* functions above, but computed column
+create function c.person_optional_missing_middle_1(p c.person, int, b int default 2, c int default 3) returns int as $$ select $2 + $3 + $4 $$ language sql immutable strict;
+create function c.person_optional_missing_middle_2(p c.person, a int, b int default 2, c int default 3) returns int as $$ select $2 + $3 + $4 $$ language sql immutable strict;
+create function c.person_optional_missing_middle_3(p c.person, a int, int default 2, c int default 3) returns int as $$ select $2 + $3 + $4 $$ language sql immutable strict;
+create function c.person_optional_missing_middle_4(p c.person, int, b int default 2, int default 3) returns int as $$ select $2 + $3 + $4 $$ language sql immutable strict;
+create function c.person_optional_missing_middle_5(p c.person, a int, int default 2, int default 3) returns int as $$ select $2 + $3 + $4 $$ language sql immutable strict;
+
 create function c.compound_type_computed_field(compound_type c.compound_type) returns integer as $$ select compound_type.a + compound_type.foo_bar $$ language sql stable;
 create function a.post_headline_trimmed(post a.post, length int default 10, omission text default '…') returns text as $$ select substr(post.headline, 0, length) || omission $$ language sql stable;
 create function a.post_headline_trimmed_strict(post a.post, length int default 10, omission text default '…') returns text as $$ select substr(post.headline, 0, length) || omission $$ language sql stable strict;

postgraphile/postgraphile/__tests__/queries/v4/procedure-computed-fields.json5

@@ -1633,4 +1633,12 @@
       },
     ],
   },
+  personById: {
+    optionalMissingMiddle1: 10,
+    optionalMissingMiddle1_2: 16,
+    optionalMissingMiddle2: 10,
+    optionalMissingMiddle3: 10,
+    optionalMissingMiddle4: null,
+    optionalMissingMiddle5: null,
+  },
 }