| Conditions | 10 | 
| Total Lines | 138 | 
| Code Lines | 107 | 
| Lines | 0 | 
| Ratio | 0 % | 
| Changes | 0 | ||
Small methods make your code easier to understand, in particular if combined with a good name. Besides, if your method is small, finding a good name is usually much easier.
For example, if you find yourself adding comments to a method's body, this is usually a good sign to extract the commented part to a new method, and use the comment as a starting point when coming up with a good name for this new method.
Commonly applied refactorings include:
If many parameters/temporary variables are present:
Complex classes like HillChart.renderGroup often do a lot of different things. To break such a class down, we need to identify a cohesive component within that class. A common approach to find such a component is to look for fields/methods that share the same prefixes, or suffixes.
Once you have determined the fields that belong together, you can apply the Extract Class refactoring. If the component makes sense as a sub-class, Extract Subclass is also a candidate, and is often faster.
| 1 | import EventEmitter from 'event-emitter-es6';  | 
            ||
| 211 | |||
| 212 |   renderGroup() { | 
            ||
| 213 | const self = this;  | 
            ||
| 214 | |||
| 215 | // Handle dragging  | 
            ||
| 216 | const dragPoint = drag<SVGGElement, DataPointInternal>()  | 
            ||
| 217 |       .on('drag', function (data) { | 
            ||
| 218 |         let { x } = event; | 
            ||
| 219 | |||
| 220 | // Check point movement, preventing it from wondering outside the main curve  | 
            ||
| 221 |         if (!x || x < 0) { | 
            ||
| 222 | x = 0;  | 
            ||
| 223 |           self.emit('home', { | 
            ||
| 224 | ...data,  | 
            ||
| 225 | y: hillFnInverse(self.yScale.invert(data.y)),  | 
            ||
| 226 | });  | 
            ||
| 227 |         } else if (x > self.chartWidth) { | 
            ||
| 228 | x = self.chartWidth;  | 
            ||
| 229 |           self.emit('end', { | 
            ||
| 230 | ...data,  | 
            ||
| 231 | x: self.xScale.invert(self.chartWidth),  | 
            ||
| 232 | y: hillFnInverse(self.yScale.invert(data.y)),  | 
            ||
| 233 | });  | 
            ||
| 234 | }  | 
            ||
| 235 | |||
| 236 | // Convert current point coordinates back to the original  | 
            ||
| 237 | // between 0 and 100 to set it in the data attribute  | 
            ||
| 238 | const invertedX = self.xScale.invert(x);  | 
            ||
| 239 | |||
| 240 | data.x = x;  | 
            ||
| 241 | |||
| 242 | data.y = self.yScale(hillFn(invertedX));  | 
            ||
| 243 | |||
| 244 | const invertedY = hillFnInverse(self.yScale.invert(data.y));  | 
            ||
| 245 | |||
| 246 |         const newInvertedCoordinates = { | 
            ||
| 247 | x: invertedX,  | 
            ||
| 248 | y: invertedY,  | 
            ||
| 249 | };  | 
            ||
| 250 | |||
| 251 | // click event  | 
            ||
| 252 |         select<SVGGElement, DataPointInternal>(this).on('click', () => { | 
            ||
| 253 |           self.emit('pointClick', { ...data, ...newInvertedCoordinates }); | 
            ||
| 254 | });  | 
            ||
| 255 | |||
| 256 |         if (!self.preview) { | 
            ||
| 257 | const selectedPoint = select<SVGGElement, DataPointInternal>(  | 
            ||
| 258 | this  | 
            ||
| 259 |           ).attr('transform', `translate(${data.x}, ${data.y})`); | 
            ||
| 260 | selectedPoint  | 
            ||
| 261 |             .select('text') | 
            ||
| 262 |             .style('text-anchor', () => { | 
            ||
| 263 |               if (textOutRange(invertedX)) { | 
            ||
| 264 | return 'end';  | 
            ||
| 265 | }  | 
            ||
| 266 | return 'start';  | 
            ||
| 267 | })  | 
            ||
| 268 |             .attr('x', (point) => | 
            ||
| 269 | calculateTextPositionForX(point.size, invertedX)  | 
            ||
| 270 | );  | 
            ||
| 271 | |||
| 272 |           self.emit('move', invertedX, invertedY); | 
            ||
| 273 | }  | 
            ||
| 274 | })  | 
            ||
| 275 |       .on('end', (data) => { | 
            ||
| 276 |         if (this.preview) { | 
            ||
| 277 | return;  | 
            ||
| 278 | }  | 
            ||
| 279 | |||
| 280 |         let { x } = event; | 
            ||
| 281 | |||
| 282 | // Check point movement, preventing it from wondering outside the main curve  | 
            ||
| 283 |         if (!x || x < 0) { | 
            ||
| 284 | x = 0;  | 
            ||
| 285 |         } else if (x > this.chartWidth) { | 
            ||
| 286 | x = this.chartWidth;  | 
            ||
| 287 | }  | 
            ||
| 288 | |||
| 289 | // Convert current point coordinates back to the original  | 
            ||
| 290 | const invertedX = this.xScale.invert(x);  | 
            ||
| 291 | data.y = this.yScale(hillFn(invertedX));  | 
            ||
| 292 | const invertedY = hillFnInverse(this.yScale.invert(data.y));  | 
            ||
| 293 | |||
| 294 |         const newInvertedCoordinates = { | 
            ||
| 295 | x: invertedX,  | 
            ||
| 296 | y: invertedY,  | 
            ||
| 297 | };  | 
            ||
| 298 | |||
| 299 |         this.emit('moved', { ...data, ...newInvertedCoordinates }); | 
            ||
| 300 | });  | 
            ||
| 301 | |||
| 302 | let group:  | 
            ||
| 303 | | Selection<SVGGElement, DataPointInternal, SVGGElement, unknown>  | 
            ||
| 304 | | undefined;  | 
            ||
| 305 | |||
| 306 |     if (this.preview) { | 
            ||
| 307 | group = this.undraggablePoint();  | 
            ||
| 308 |     } else { | 
            ||
| 309 | // Create group consisted of a circle and a description text, where  | 
            ||
| 310 | // the data attributes determine the position of them on the curve  | 
            ||
| 311 | group = this.svg  | 
            ||
| 312 |         .selectAll('.hill-chart-group') | 
            ||
| 313 | .data(this.data)  | 
            ||
| 314 | .enter()  | 
            ||
| 315 |         .append('g') | 
            ||
| 316 |         .attr('class', 'hill-chart-group') | 
            ||
| 317 |         .attr('transform', (data) => { | 
            ||
| 318 | data.x = this.xScale(data.x);  | 
            ||
| 319 | data.y = this.yScale(data.y);  | 
            ||
| 320 |           return `translate(${data.x}, ${data.y})`; | 
            ||
| 321 | })  | 
            ||
| 322 | .call(dragPoint);  | 
            ||
| 323 | }  | 
            ||
| 324 | |||
| 325 | group  | 
            ||
| 326 |       .append('circle') | 
            ||
| 327 |       .attr('class', 'hill-chart-circle') | 
            ||
| 328 |       .attr('fill', (data) => data.color) | 
            ||
| 329 |       .attr('cx', 0) | 
            ||
| 330 |       .attr('cy', 0) | 
            ||
| 331 |       .attr('r', (data) => data.size || DEFAULT_SIZE); | 
            ||
| 332 | |||
| 333 | group  | 
            ||
| 334 |       .append('text') | 
            ||
| 335 | .text((data) => data.description)  | 
            ||
| 336 |       .attr('x', (data) => | 
            ||
| 337 | calculateTextPositionForX(  | 
            ||
| 338 | data.size || DEFAULT_SIZE,  | 
            ||
| 339 | this.xScale.invert(data.x)  | 
            ||
| 340 | )  | 
            ||
| 341 | )  | 
            ||
| 342 |       .style('text-anchor', (data) => { | 
            ||
| 343 |         if (textOutRange(this.xScale.invert(data.x))) { | 
            ||
| 344 | return 'end';  | 
            ||
| 345 | }  | 
            ||
| 346 | return 'start';  | 
            ||
| 347 | })  | 
            ||
| 348 |       .attr('y', calculateTextMarginForY()); | 
            ||
| 349 | }  | 
            ||
| 411 |