Merge branch '1940-add-split_part-formula-function' into 'develop'

Resolve "Add split_part formula function"

Closes #1940

See merge request baserow/baserow!1646

backend/src/baserow/contrib/database/formula/ast/function_defs.py

@@ -151,6 +151,7 @@ def register_formula_functions(registry):
     registry.register(BaserowEven())
     registry.register(BaserowOdd())
     registry.register(BaserowTrunc())
+    registry.register(BaserowSplitPart())
     registry.register(BaserowLn())
     registry.register(BaserowExp())
     registry.register(BaserowLog())
@@ -854,6 +855,50 @@ class BaserowFloor(OneArgumentBaserowFunction):
         return Floor(arg, output_field=int_like_numeric_output_field())
 
 
+class BaserowSplitPart(ThreeArgumentBaserowFunction):
+    type = "split_part"
+    arg1_type = [BaserowFormulaTextType]
+    arg2_type = [BaserowFormulaTextType]
+    arg3_type = [BaserowFormulaNumberType]
+
+    def type_function(
+        self,
+        func_call: BaserowFunctionCall[UnTyped],
+        arg1: BaserowExpression[BaserowFormulaTextType],
+        arg2: BaserowExpression[BaserowFormulaTextType],
+        arg3: BaserowExpression[BaserowFormulaNumberType],
+    ) -> BaserowExpression[BaserowFormulaType]:
+        return func_call.with_valid_type(
+            BaserowFormulaTextType(
+                nullable=arg1.expression_type.nullable
+                or arg2.expression_type.nullable
+                or arg3.expression_type.nullable
+            )
+        )
+
+    def to_django_expression(
+        self, arg1: Expression, arg2: Expression, arg3: Expression
+    ) -> Expression:
+        return Case(
+            When(
+                condition=(
+                    LessThanEqualOrExpr(
+                        arg3, Value(0), output_field=fields.BooleanField()
+                    )
+                ),
+                then=Value(""),
+            ),
+            default=Func(
+                arg1,
+                arg2,
+                trunc_numeric_to_int(arg3),
+                function="SPLIT_PART",
+                output_field=fields.CharField(),
+            ),
+            output_field=fields.CharField(),
+        )
+
+
 class BaserowTrunc(OneArgumentBaserowFunction):
     type = "trunc"
     arg_type = [BaserowFormulaNumberType]

backend/tests/baserow/contrib/database/formula/test_baserow_formula_results.py

@@ -358,6 +358,15 @@ VALID_FORMULA_TESTS = [
         "http://example.com/wiki/Se%c3%b1or",
     ),
     ("encode_uri_component('Hello World')", "Hello%20World"),
+    ("split_part('John, Jane, Matthew', ', ', 2)", "Jane"),
+    ("split_part('John, Jane, Matthew', 'xxx', 2)", ""),
+    ("split_part('John, Jane, Matthew', ', ', -1.5)", ""),
+    ("split_part('John, Jane, Matthew', ', ', -1)", ""),
+    ("split_part('John, Jane, Matthew', ', ', 0)", ""),
+    ("split_part('John, Jane, Matthew', ', ', 1.5)", "John"),
+    ("split_part('John, Jane, Matthew', ', ', 3.5)", "Matthew"),
+    ("split_part('John, Jane, Matthew', ', ', 4.5)", ""),
+    ("split_part('John, Jane, Matthew', ', ', 9999)", ""),
 ]
 
 

changelog/entries/unreleased/feature/1940_add_split_part_formula_function.json

@@ -0,0 +1,7 @@
+{
+    "type": "feature",
+    "message": "add split_part formula function",
+    "issue_number": 1940,
+    "bullet_points": [],
+    "created_at": "2023-09-12"
+}

web-frontend/locales/en.json

@@ -337,6 +337,7 @@
     "formulaFunctions": {
         "upperDescription": "Returns its argument in upper case.",
         "lowerDescription": "Returns its argument in lower case.",
+        "splitPartDescription": "Extracts a segment from a delimited string based on a delimiter and index (numeric indicator indicating which element from string should be returned)",
         "concatDescription": "Returns its arguments joined together as a single piece of text.",
         "addDescription": "Returns its two arguments added together.",
         "minusDescription": "Returns its two arguments subtracted.",

web-frontend/modules/database/formula/functions.js

@@ -86,6 +86,29 @@ export class BaserowLower extends BaserowFunctionDefinition {
   }
 }
 
+export class BaserowSplitPart extends BaserowFunctionDefinition {
+  static getType() {
+    return 'split_part'
+  }
+
+  getDescription() {
+    const { i18n } = this.app
+    return i18n.t('formulaFunctions.splitPartDescription')
+  }
+
+  getSyntaxUsage() {
+    return ['split_part(text, delimiter, position)']
+  }
+
+  getExamples() {
+    return ["split_part('John, Jane, Michael', ', ', 2) = 'Jane'"]
+  }
+
+  getFormulaType() {
+    return 'text'
+  }
+}
+
 export class BaserowConcat extends BaserowFunctionDefinition {
   static getType() {
     return 'concat'

web-frontend/modules/database/plugin.js

@@ -130,6 +130,7 @@ import {
   BaserowLessThan,
   BaserowLessThanOrEqual,
   BaserowLower,
+  BaserowSplitPart,
   BaserowMinus,
   BaserowMultiply,
   BaserowNot,
@@ -462,6 +463,7 @@ export default (context) => {
     'formula_function',
     new BaserowEncodeUriComponent(context)
   )
+  app.$registry.register('formula_function', new BaserowSplitPart(context))
   // Number functions
   app.$registry.register('formula_function', new BaserowMultiply(context))
   app.$registry.register('formula_function', new BaserowDivide(context))

web-frontend/test/unit/database/formula/formulaFunctions.spec.js

@@ -93,6 +93,7 @@ describe('Formula Functions Test', () => {
       'button',
       'get_link_label',
       'get_link_url',
+      'split_part',
     ]
     const frontendFunctionTypes = Object.keys(
       testApp.store.$registry.getAll('formula_function')